GNU Emacs FAQ for MS Windows

1.1 Why support GNU Emacs on Windows?

It is not our goal to “help Windows users” by making text editing on Windows more convenient. We aim to replace proprietary software, not to enhance it. So why support GNU Emacs on Windows?

We hope that the experience of using GNU Emacs on Windows will give programmers a taste of freedom, and that this will later inspire them to move to a free operating system such as GNU/Linux. That is the main valid reason to support free applications on nonfree operating systems.

1.2 Which versions of Windows are supported?

Emacs 29.1.90 is known to run on all versions of Windows 9X from Windows 98 onward, and all versions of the NT family starting from NT 4.0; this includes all the modern versions from Windows XP and on. The Windows port is built using the Win32 API and supports most features of the X version, including variable width fonts, images and tooltips. Emacs on Windows can be compiled as either a 64-bit or a 32-bit executable.

1.3 What other versions of Emacs run on Windows?

See Cygwin.

Emacs can also be compiled for MSDOS. When run on recent MS Windows, it supports long file names, and uses the Windows clipboard. See the msdos directory in the Emacs sources for building instructions (requires DJGPP).

2.1 Where can I download Emacs?

You can download Emacs releases from ftp.gnu.org mirrors. They are distributed as compressed tar files, digitally signed by the maintainer who made the release.

Pre-compiled binaries for MS Windows may be made available on a best-effort basis in the windows subdirectory of the above ftp site (as zip files digitally signed by the person who built them). See the README file in that directory for more information. Building Emacs from source yourself should be straightforward, following the instructions in the nt directory, so we encourage you to give it a try. See How can I compile Emacs myself?.

The development version of Emacs is available from Savannah, the GNU development site.

2.2 How can I compile Emacs myself?

To compile Emacs on a 64-bit version of Windows 7 or newer, we recommend to use the MinGW-w64 port of GCC and Binutils with the MSYS2 suite of tools. For the details, see the file nt/INSTALL.W64 in the Emacs source distribution.

If you need to build or run Emacs on MS Windows before Windows 7, you have to use the MinGW port of GCC and the MSYS suite of tools. The file nt/INSTALL in Emacs source distribution contains the details.

Support for displaying images, as well as XML/HTML rendering and TLS networking requires external libraries, the headers and import libraries for which will need to be installed where your compiler can find them. Again, the details, including URLs of sites where you can download these libraries are in nt/INSTALL.W64 or nt/INSTALL. See Other useful ports, for auxiliary tools you may wish to install and use in conjunction with Emacs.

After unpacking the source, or checking out of the repository, be sure to read the instructions in nt/README and the respective install file.

2.3 How do I use a debugger on Emacs?

By default, Emacs is compiled with debugging on, and optimizations enabled. The optimizations may interfere with some types of debugging; the debugger may not show clearly where it is, or may not be able to inspect certain variables. If this is the case, reconfigure with CFLAGS='-O0 -g3'

The file etc/DEBUG contains general debugging hints, as well as specific notes about debugging Emacs.

GDB is the GNU debugger, which can be used to debug Emacs when it has been compiled with GCC. The best results will be obtained if you start gdb from the src directory as gdb ./emacs.exe. This will load the init file .gdbinit¹ in that directory, to define some extra commands for working with lisp while debugging, and set up breakpoints to catch abnormal aborts.

A Windows port of GDB is installed with MinGW64-w64 and MSYS2 (‘mingw-w64-<arch>-toolchain’ group) or can be found on MinGW download sites and on some others.

3.1 How do I unpack the distributions?

The binary distributions are distributed as zip files, which are handled natively by Windows XP and later. For earlier versions, there are many tools that can handle the zip format, from InfoZip’s command line unzip tool, to 7zip’s multi-format graphical archive explorer. (Although popular, WinZip has caused problems with line-ends in the past, and is not Free software, so we do not recommend it.)

Source distributions are distributed as .tar.gz or .tar.xz files. 7zip and similar multi-format graphical tools can handle these, or you can get Windows ports of the command line gzip and tar tools from multiple sources, or use bsdtar. See Other useful ports.

The command to unpack a source distribution from the command line is:

tar xzf emacs-29.1.90.tar.gz

If this does not work with the versions of tar and gzip that you have, you may need to try a two step process:

gzip -dc emacs-29.1.90.tar.gz | tar xf -

You may see many messages from tar complaining about being unable to change the modification time on directories, and from gzip complaining about a broken pipe. These messages are usually harmless, caused by incomplete ports that are not fully aware of the limitations of Windows.

And here’s an example of using bsdtar (from the ‘libarchive’ package) to unpack a .tar.xz archive:

bsdtar -xf emacs-29.1.90.tar.xz

Expect bsdtar to unpack the whole distribution without any complaints.

Once you unpack the source distribution, look in the nt directory for build instructions.

3.2 How do I install Emacs after unpacking the binary zip?

You can run Emacs without any extra steps, but if you want icons in your Start Menu, or for Emacs to detect the image libraries that are already installed on your system as part of GTK+, then you should run the program addpm.exe, which is usually installed into the same bin directory with emacs.exe.

3.3 How do I get image support?

Emacs has built in support for XBM and PBM/PGM/PPM images. This is sufficient to see the monochrome splash screen and tool-bar icons. Since v22.2, the official precompiled binaries for Windows have bundled libXpm, which is required to display the color versions of those images.

Emacs is compiled to recognize JPEG, PNG, GIF, TIFF, and RSVG images also, but displaying these image types require external DLLs which are not bundled with Emacs. See Other useful ports.

3.4 What is my init file?

When Emacs starts up, it attempts to load and execute the contents of a file commonly called .emacs (though it may have other names, see Where do I put my init file?) which contains any customizations you have made. You can manually add lisp code to your .emacs, or you can use the Customization interface accessible from the Options menu. If the file does not exist, Emacs will start with the default settings.

3.5 Where do I put my init file?

On Windows, the .emacs file may be called _emacs for backward compatibility with DOS and FAT filesystems where filenames could not start with a dot. Some users prefer to continue using such a name due to historical problems various Windows tools had in the past with file names that begin with a dot. The init file may also be called .emacs.d/init.el. Many of the other files that are created by Lisp packages are stored in the .emacs.d directory too, which keeps all your Emacs related files in one place.

All the files mentioned above should go in your HOME directory. The HOME directory is determined by following the steps below:

1. If the environment variable HOME is set, use the directory it indicates.
2. If the registry entry HKCU\SOFTWARE\GNU\Emacs\HOME is set, use the directory it indicates.
3. If the registry entry HKLM\SOFTWARE\GNU\Emacs\HOME is set, use the directory it indicates. Not recommended, as it results in users sharing the same HOME directory.
4. If C:\.emacs exists, then use C:/. This is for backward compatibility, as previous versions defaulted to C:/ if HOME was not set.
5. Use the user’s AppData directory, usually a directory called AppData under the user’s profile directory, the location of which varies according to Windows version and whether the computer is part of a domain.

Within Emacs, ~ at the beginning of a file name is expanded to your HOME directory, so you can always find your .emacs file by typing the command C-x C-f ~/.emacs.

3.6 Troubleshooting init file problems

If you’ve set HOME to a directory using one of the above methods, and Emacs still doesn’t load your init file, the first thing you should do is check to see what Emacs thinks HOME is set to. You can do this by evaluating the following expression in the *scratch* buffer using C-x C-e:

(getenv "HOME")

Look carefully at what is printed in the echo area, and make sure the value is valid. For example, if the value has trailing whitespace, Emacs won’t be able to find the directory. Also, be sure that the value isn’t a relative drive letter (e.g., d: without a backslash or a forward slash after the colon); if it is, then HOME is going to be whatever the current directory on that drive is, which is likely not what you want to happen.

3.7 How do I associate files with Emacs?

The recommended way to associate files is to associate them with emacsclientw.exe. In order for this to work when Emacs is not yet started, you will also need to set the environment variable ALTERNATE_EDITOR to runemacs.exe. To open files in a running instance of Emacs, you will need to add the following to your init file:

(server-start)

• For use with Internet Explorer

3.8 How do I use find-file to open files that are on the Desktop?

The location of the Desktop varies between different versions of Windows, and in a corporate environment can be moved around by the network administrator. On latest Windows versions, you can use the value of the USERPROFILE environment variable to find where the desktop might be:

C-x C-f $USERPROFILE/Desktop

If this doesn’t work, then you probably have to forgo the keyboard just this once, and either drag a file onto the Emacs frame from the desktop, or use the file dialog (displayed when you use the toolbar or menu by default). Once you have a file from the Desktop inside Emacs, C-x C-f will quickly reveal where your desktop is kept.

3.9 How can I modify Windows to act more like X?

• How do I make the active window follow the mouse?
• How do I swap CapsLock and Control?

3.10 How can I modify Emacs to act more like a Windows app?

Many beginning users find Emacs difficult to use because its user interface is different in many ways. Emacs predates most UI standards, and experienced Emacs users are used to the way things are, so changing the defaults is difficult. Most of the “standard” behavior can be approximated in Emacs after some configuring though.

• Highlighting the selection
• Standard Windows key bindings

3.11 Window operations

The function w32-send-sys-command can be used to simulate choosing commands from the system menu (in the top left corner of the Window) and a few other system wide functions. It takes an integer argument, the value of which should be a valid WM_SYSCOMMAND message as documented in Microsoft’s API documentation.

3.12 How do I uninstall Emacs?

Emacs does not come with an uninstall program. No files are installed outside of the directories you find in the binary zip archive, so deleting those directories is sufficient to clean away the files. If you ran addpm, you’ll need to delete the Start Menu group too. The registry entries inserted by addpm will not cause any problems if you leave them there, but for the sake of completeness, you can use regedit to remove the keys under HKEY_LOCAL_MACHINE or HKEY_CURRENT_USER: SOFTWARE\GNU\Emacs, and the key HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\App Paths\emacs.exe if it exists.

3.13 When I run Emacs nothing happens

Emacs could have failed to run for a number of reasons. The most common symptom is that, when Emacs is started, the cursor changes for a second but nothing happens. If this happens to you, it is quite likely that the distribution was unpacked incorrectly.

Check for the following to see if there was a problem during unpacking:

1. Be sure to disable the CR/LF translation or the executables will be unusable. Older versions of WinZipNT would enable this translation by default. If you are using WinZipNT, disable it.
2. Check that filenames were not truncated to 8.3. For example, there should be a file CONTRIBUTE in the top level directory; if this has been truncated to CONTRIBU or CONTRI~1, your distribution has been corrupted while unpacking and Emacs will not start.

If it is still not working, send mail to the help-gnu-emacs@gnu.org mailing list, describing what you’ve done, and what you are seeing. (The more information you send the more likely it is that you’ll receive a helpful response.)

3.14 Does Emacs contain a virus?

There have been reports in the past that some virus scanners claim that the Emacs distribution has a virus. This is extremely unlikely if you have downloaded Emacs from the GNU FTP site or one of its mirrors and the GPG signature for it is valid and listed in the GNU keyring, unless perhaps it is a new release made in the last few days, in which case you should exercise more caution and report the problem. Past problems seem to have been caused by virus checkers running into a buffer size limit when unpacking large tar.gz files for scanning, and reporting the failure as an “unknown virus”.

3.15 What known problems are there with anti-virus software?

Anti-virus and firewall software can block Emacs from starting subprocesses and opening network connections. Most such products have an Advanced mode where they will prompt you rather than silently blocking. In some cases the “scan all files” or “auto protect” option of anti-virus programs has caused failures running shell related commands within Emacs. See Why is nothing happening when I enter shell commands?.

4.1 Emacs in console mode goes beyond the window size

The variable w32-use-full-screen-buffer controls whether Emacs uses the window size or buffer size to determine the number of lines on screen. Normally the window size is correct, but when running Emacs over some telnet servers, the buffer size needs to be used. Emacs tries to guess the correct value at startup, but if it guesses wrong, you can customize that variable yourself.

4.2 What do I do if I have problems with my mouse buttons?

Emacs assigns bindings assuming a three button mouse. On Windows, if a two button mouse is detected, a hack is enabled which lets you simulate the third button by pressing both mouse buttons simultaneously. w32-mouse-button-tolerance defines the timeout for what is considered “simultaneous”. You can check how many buttons Emacs thinks your mouse has with C-h v w32-num-mouse-buttons.

If you find yourself needing the mouse-3 bindings more often than mouse-2, you can swap the buttons with the following code in your init file:

(setq w32-swap-mouse-buttons t)

4.3 How do I cut and paste text with NUL characters?

If you attempt to cut and paste text with NUL characters embedded in it, then the text will be truncated at the first NUL character. This is a limitation of the Windows clipboard, and does not affect killing and yanking from the kill-ring within Emacs.

4.4 How can I fix garbled text yanked from the clipboard?

You can try set-selection-coding-system, but generally such corruption is a thing of the past, as Emacs uses Unicode for the clipboard by default now.

4.5 How do I change the sound of the Emacs beep?

You can use the function set-message-beep to change the sound that Emacs uses for its beep. This affects both console and GUI frames. The doc string contains a list of the system sounds you can use.

5.1 Font names

Fonts in Emacs 22 and earlier are named using the X Logical Font Description (XLFD) format. Emacs on Windows ignores many of the fields, and populates them with * when listing fonts. Former maintainer Andrew Innes wrote this explanation of what each field in the font string means and how Emacs treated them back in 19.34. Since then, multilingual support and a redisplay overhaul to support variable width fonts have changed things slightly; more character sets are recognized (and the old pseudo character sets are deprecated), and the resolution fields are used to calculate the difference between point and pixel sizes, but normally you should leave these at the system default. The foundry field is also populated with an indication of whether the font is outline (.TTF, .ATM) or raster (.FON) based when fonts are listed, which may let you differentiate between two fonts with the same name and different technologies.

Starting with Emacs 23, the preferred font name format is the simpler and more flexible fontconfig format. XLFD names will continue to be supported for backward compatibility.

XLFD: -*-Courier New-normal-r-*-*-13-*-*-*-c-*-iso8859-1
Fontconfig: Courier New-13

To find the XFLD name for a font, you can execute the following in the *scratch* buffer by pressing C-j at the end of the line:

(x-select-font nil t)

To see a complete list of fonts, execute the following Lisp snippet by typing it into the *scratch* buffer and pressing C-x C-e at the end of the second line:

(dolist (font (x-list-fonts "*"))
  (insert (format "%s\n" font)))

The command line options and frame-parameters for changing the default font in Emacs are documented in the manual. Fonts can also be used when defining faces, though family and size are generally specified individually there. In addition, Emacs on Windows reads the registry to find X Resources. This is also documented in the manual.

5.2 How can I get bold and italic fonts to work?

Emacs will only use the italic (and bold) versions of a font automatically if it has the same width as the normal version. Many fonts have italic and bold versions that are slightly wider. It will also only use real bold and italic fonts by default, where other applications may use synthesized variations that are derived from the normal font. To enable more italic and bold fonts to be displayed, you can enable synthesized fonts and manually set the font for italic, bold and bold-italic as follows:

(setq w32-enable-synthesized-fonts t)
(set-face-font 'italic "-*-Courier New-normal-i-*-*-11-*-*-*-c-*-iso8859-1")
(set-face-font 'bold-italic "-*-Courier New-bold-i-*-*-11-*-*-*-c-*-iso8859-1")

The w32-enable-synthesized-fonts variable is obsolete starting from Emacs 24.4, as Emacs no longer has this limitation.

5.3 Multilingual font support

• Is it possible to display all the supported languages?
• How do I get Emacs to display non-latin characters?
• Where can I find fonts for other languages?
• How do I use third party programs to display multibyte characters?
• Can I use a font with a name in my language?

(create-fontset-from-fontset-spec
 "-*-Courier New-normal-r-*-*-12-*-*-*-c-*-fontset-most,
 latin-iso8859-2:-*-Courier New-normal-r-*-*-12-*-*-*-c-*-iso8859-2,
 latin-iso8859-3:-*-Courier New-normal-r-*-*-12-*-*-*-c-*-iso8859-3,
 latin-iso8859-4:-*-Courier New-normal-r-*-*-12-*-*-*-c-*-iso8859-4,
 cyrillic-iso8859-5:-*-Courier New-normal-r-*-*-12-*-*-*-c-*-iso8859-5,
 greek-iso8859-7:-*-Courier New-normal-r-*-*-12-*-*-*-c-*-iso8859-7,
 latin-iso8859-9:-*-Courier New-normal-r-*-*-12-*-*-*-c-*-iso8859-9,
 japanese-jisx0208:-*-MS Gothic-normal-r-*-*-12-*-*-*-c-*-jisx0208-sjis,
 katakana-jisx0201:-*-MS Gothic-normal-r-*-*-12-*-*-*-c-*-jisx0208-sjis,
 latin-jisx0201:-*-MS Gothic-normal-r-*-*-12-*-*-*-c-*-jisx0208-sjis,
 japanese-jisx0208-1978:-*-MS Gothic-normal-r-*-*-12-*-*-*-c-*-jisx0208-sjis,
 korean-ksc5601:-*-Gulim-normal-r-*-*-12-*-*-*-c-*-ksc5601-*,
 chinese-gb2312:-*-MS Song-normal-r-*-*-12-*-*-*-c-*-gb2312-*,
 chinese-big5-1:-*-MingLiU-normal-r-*-*-12-*-*-*-c-*-big5-*,
 chinese-big5-2:-*-MingLiU-normal-r-*-*-12-*-*-*-c-*-big5-*" t)

5.4 How can I have Emacs use a font menu like on X?

Place the following in your init file:

(setq w32-use-w32-font-dialog nil)

• How can I add my font to the font menu?

(setq w32-fixed-font-alist
   (append w32-fixed-font-alist
      '(("Monotype.com"
         ("8" "-*-Monotype.com-normal-r-*-*-11-*-*-*-c-iso8859-1")
         ("9" "-*-Monotype.com-normal-r-*-*-12-*-*-*-c-iso8859-1")
         ("10" "-*-Monotype.com-normal-r-*-*-13-*-*-*-c-iso8859-1")
         ("11" "-*-Monotype.com-normal-r-*-*-15-*-*-*-c-iso8859-1")))))

5.5 How can I control CR/LF translation?

There are a number of methods by which you can control automatic CR/LF translation in Emacs, a situation that reflects the fact that the default support was not very robust in the past. For a discussion of this issue, take a look at this collection of email messages on the topic.

• Automatic CR/LF translation
• CR/LF translation by file system

7.1 Quoting issues

The quoting rules for native Windows shells and Cygwin shells have some subtle differences. When Emacs spawns subprocesses, it tries to determine whether the process is a Cygwin program and changes its quoting mechanism appropriately.

7.2 Programs reading input hang

Programs that explicitly use a handle to the console (CON or CON:) instead of stdin and stdout cannot be used as subprocesses to Emacs, and they will also not work in shell-mode. The default ftp client on Windows is an example of such a program - this ftp program is mostly fine for use with ange-ftp or tramp, but not for M-x ftp (see How do I use FTP within Emacs). There is no convenient way for either Emacs or any shell used in shell-mode to redirect the input and output of such processes from the console to input and output pipes. The only workaround is to use a different implementation of the program that does not use the console directly. Microsoft’s new PowerShell appears to be another such program, so that cannot be used as a replacement shell for Emacs.

7.3 Buffering in shells and subprocesses

You may notice that some programs, when run in a shell in shell-mode, have their output buffered (e.g., people have found this happening to them with sql-mode). When the program has a lot of output, it overflows the buffering and gets printed to the shell buffer; however, if the program only outputs a small amount of text, it will remain buffered and won’t appear in the shell buffer. The same can happen in other subprocesses that themselves run other programs as subprocesses, for example when using cvs from Emacs, which is itself configured to use ssh, password prompts fail to appear when expected, and cvs appears to hang.

Although it may at first seem like the shell is buffering the output from the program, it is actually the program that is buffering output. The C runtime typically decides how to buffer output based upon whether stdout is bound to a handle to a console window or not. If bound to a console window, output is buffered line by line; if bound to a block device, such as a file, output is buffered block by block.

In a shell buffer, stdout is a pipe handle and so is buffered in blocks. If you would like the buffering behavior of your program to behave differently, the program itself is going to have to be changed; you can use setbuf and setvbuf to manipulate the buffering semantics.

Some programs handle this by having an explicit flag to control their buffering behavior, typically -i for interactive, or by a special environment variable. Other programs manage to detect that they are running under Emacs, by using ‘getenv("emacs")’ internally. Look in the program’s documentation for the way around this issue.

• Perl script buffering

# Turn all buffering off.
select((select(STDOUT), $| = 1)[0]);
select((select(STDERR), $| = 1)[0]);
select((select(STDIN), $| = 1)[0]);

7.4 16-bit subprocesses accessing the floppy drive

If you are finding the 16 bit DOS subprocesses cause your A: drive to be accessed, hanging Emacs until the read times out if there is no floppy in the drive, check to see if your virus software is causing the problem.

7.5 Killing subprocesses on Windows 95/98/Me

Emacs cannot guarantee that a subprocess gets killed on Windows 95 and its descendants, and it is a difficult limitation to work around. To avoid problems on these systems, you should let subprocesses run to completion including explicitly exiting shells before killing the associated buffer.

If you find that while shutting down, Windows complains that there is a running cmdproxy.exe even though you carefully exited all shells and none were showing in Task Manager before the shutdown, this could be due to buggy interaction with your virus scanner.

7.6 Sending EOF to subprocesses

When an EOF is sent to a subprocess running in an interactive shell with process-send-eof, the shell terminates unexpectedly as if its input was closed. This affects the use of C-c C-d in shell buffers. See this discussion for more details.

7.7 How do I use a shell in Emacs?

You can start an interactive shell in Emacs by typing M-x shell. By default, this will start the standard Windows shell cmd.exe. Emacs uses the SHELL environment variable to determine which program to use as the shell. To instruct Emacs to use a non-default shell, you can either set this environment variable, or customize explicit-shell-file-name. You can also customize shell-file-name to change the shell that will be used by subprocesses that are started with shell-command and related non-interactive shell commands.

• bash

(defun my-shell-setup ()
  "For Cygwin bash under Emacs 20"
  (setq comint-scroll-show-maximum-output 'this)
  (make-variable-buffer-local 'comint-completion-addsuffix))
  (setq comint-completion-addsuffix t)
  ;; (setq comint-process-echoes t) ;; reported that this is no longer needed
  (setq comint-eol-on-send t)
  (setq w32-quote-process-args ?\")

(add-hook 'shell-mode-hook 'my-shell-setup)

    (setenv "PID" nil)

7.8 How do I use Cygwin style paths in Emacs?

The package cygwin-mount.el teaches Emacs about Cygwin mount points.

7.9 How do I make dired use my ls program?

Dired uses an internal lisp implementation of ls by default on Windows. For consistent display of symbolic links and other information with other programs (eg Cygwin) and performance reasons, you may want to use a Windows port of ls instead.

(setq ls-lisp-use-insert-directory-program t)      ;; use external ls
(setq insert-directory-program "c:/cygwin/bin/ls") ;; ls program name

7.10 How do I prevent shell commands from being echoed?

Some shells echo the commands that you send to them, and the echoed commands appear in the output buffer. In particular, the default shells, command.com and cmd.exe, have this behavior.

To prevent echoed commands from being printed, you can place the following in your init file:

    (defun my-comint-init ()
      (setq comint-process-echoes t))
    (add-hook 'comint-mode-hook 'my-comint-init)

If shell-mode still is not stripping echoed commands, then you’ll have to explicitly tell the shell to not echo commands. You can do this by setting the explicit-SHELL-args variable appropriately; where SHELL is the value of your SHELL environment variable (do a M-: (getenv "SHELL") to see what it is currently set to). Assuming that you are on NT and that your SHELL environment variable is set to cmd.exe, then placing the following in your init file will tell cmd.exe to not echo commands:

    (setq explicit-cmd.exe-args '("/q"))

The comint package will use the value of this variable as an argument to cmd.exe every time it starts up a new shell; the /q is the argument to cmd.exe that stops the echoing (invoking ‘cmd /?’ in a shell will show you all of the command line arguments to cmd.exe).

Note that this variable is case sensitive; if the value of your SHELL environment variable is CMD.EXE instead, then this variable needs to be named explicit-CMD.EXE-args instead.

7.11 How can I make shell completion use forward slashes?

The character appended to directory names when completing in a shell buffer is controlled by the variable comint-completion-addsuffix. See its documentation (with C-h v) for details.

7.12 Why do I get incorrect DOS version messages?

This might happen if, for example, you invoke nmake in a shell and it tries to create sub-shells. The problem happens because when the shell is initially created, the first argument to the shell is not the directory in which the shell program resides. When this happens, command.com fabricates a value for its COMSPEC environment variable that is incorrect. Then, when other programs go to use COMSPEC to find the shell, they are given the wrong value.

The fix for this is to either prevent any arguments from being sent to the shell when it starts up (in which case command.com will use a default, and correct, value for COMSPEC), or to have the first argument be the directory in which the shell executable resides.

7.13 Why is nothing happening when I enter shell commands?

Some anti-virus software has been reported to cause problems with shells in the past. Try turning off options such as “Scan all files”. See What known problems are there with anti-virus software?.

8.1 How do I use mail in Emacs?

Emacs comes with several options for reading and writing mail. These are documented in the manual, and the choice of which method to use depends on personal taste. There are some issues specific to Windows however, related to the fact that Windows machines do not have the mail infrastructure that is commonly installed on other platforms, so mail will not work without some configuration.

• Outgoing mail
• Incoming mail with Rmail and POP3
• Incoming mail with Gnus
• Other incoming mail options

(setq user-full-name "Your full name")
(setq user-mail-address "Your@email.address")
(setq smtpmail-default-smtp-server "domain.name.of.your.smtp.server")

(setq send-mail-command 'smtpmail-send-it) ; For mail-mode (Rmail)
(setq message-send-mail-function 'smtpmail-send-it) ; For message-mode (Gnus)

(setenv "MAILHOST" "domain.name.of.your.pop3.server")
(setq rmail-primary-inbox-list '("po:your logon id"))
(setq rmail-remote-password-required t)

8.2 How do I open attachments in Gnus?

In your HOME directory create a file called .mailcap, with contents like the following:

application/zip; "C:/Program Files/7-Zip/7zFM.exe"
video/*; "C:/Program Files/VideoLAN/VLC/vlc.exe"

Warning: Associating MIME types with start or other generic Windows commands to open arbitrary files might seem like a good idea, but it leaves your system as open to attack as Outlook Express was at its worst. Especially dangerous is associating application/* or */* in this way.

8.3 How do I use FTP within Emacs?

Windows built in FTP client can be used with ange-ftp. Ange-ftp is the Emacs package that provides FTP connectivity to tramp, a multi-protocol remote file access package for Emacs that is enabled by default.

The Windows FTP client does have problems with some firewalls, due to lack of passive mode support, so you may want to try an alternative ftp client instead. Make sure that the client you are trying is in your PATH before the default Windows client, or rename the default Windows client to avoid it getting in the way. Alternatively you can customize ange-ftp-ftp-program-name to the full path to the version you are trying. See Other useful ports.

8.4 How do I use Tramp to work in Emacs via SSH?

Tramp can use a number of protocols to connect to remote machines to read files and even run commands on those files remotely. A popular one is ssh. As well as Cygwin versions of openssh, you can use PuTTY’s command line plink program as the ssh client. The relevant methods to use in tramp-default-method or tramp-default-method-alist for these options are:

• openssh
  • scp Uses scp for copying, ssh for shell operations.
  • ssh Uses ssh with encoding on stdin/stdout for file transfer.
• PuTTY
  • pscp Uses pscp for copying, plink for shell operations.
  • plink Uses plink with encoding on stdin/stdout for file transfer.

8.5 How do I use telnet with Emacs?

To use telnet-mode on Windows, you need a telnet client that uses stdin and stdout for input and output. The default Windows client is a Windows application, and will not work as a subprocess. Several options exist, but information that was formerly in this FAQ is out of date now, so no concrete pointers are available.

9.1 How do I use TeX with Emacs?

You will need an implementation of TeX for Windows. A number of implementations are listed on the TeX Users Group website.

9.2 How do I perform spell checks?

Emacs has support for spell checking on demand (ispell) and as your type (flyspell). Both packages depend on a copy of ispell 3.2 or a compatible spell-checking program. GNU Aspell is a popular choice these days, outdated Windows installers are available from the official site. Another possibility is Hunspell, which is available from the ezwinports site. If you’re using the MSYS2 distribution, you can install a recent version of either GNU Aspell or Hunspell through the package manager Pacman. See Other useful ports.

Once installed, you will need to configure ispell-program-name to tell ispell and flyspell to use aspell or hunspell as a replacement for ispell. You can include the full path to the aspell/hunspell binary, which means you do not need to add its installation directory to the PATH.

9.3 Emacs and encryption

GNU Privacy Guard is a Free replacement for PGP, with Windows binaries available. See https://www.gnupg.org/.

9.4 Why doesn’t my wheel mouse work in Emacs?

Some wheel mice ship with default settings that do not send the standard wheel events to programs, but instead try to simulate scroll bar events. Usually this is configurable from the hardware specific pages on the mouse control panel. The middle button is often mapped in the same settings to have some functionality other than sending middle mouse button events. In some cases, uninstalling the manufacturer’s drivers and telling Windows to use the generic USB or PS/2 drivers is the only way to make the mouse work properly.

9.5 How do I use grep with Emacs?

The best way to use M-x grep with Emacs is to download a port of GNU grep. See Other useful ports.

If you want a quick solution without installing extra tools, a poor substitute that works for simple text searches is to specify the built in Windows command findstr as the command to run at the M-x grep prompt. Normally you will want to use the /n argument to findstr, to have it print the line numbers for each hit.

• How do I do a recursive grep?

10.1 How do I use Emacs with Microsoft Visual C++

There are two ways you can use Emacs in conjunction with MSVC. You can use Emacs as the editor, and do everything else in the DevStudio IDE. Or you can use Emacs as an IDE, calling the MSVC command line tools to build your project.

• Emacs as the text editor for DevStudio
• Using MSVC command line tools from Emacs

nmake -f ProjectName.mak

nmake -f ProjectName.mak CFG="ProjectName - Win32 Release"

;; Set up for Visual C++ compiling
(setq compile-command "nmake -f ")

PROJECT=MyProject
all: debug
debug: FORCE
        nmake /f $(PROJECT).mak CFG="$(PROJECT) - Win32 Debug"
release: FORCE
        nmake /f $(PROJECT).mak CFG="$(PROJECT) - Win32 Release"
FORCE:

10.2 Emacs and Borland C++ Builder

Jonathan Arnold has written an EmacsEdit “expert” for interfacing C++ Builder and Emacs.

10.3 Is there a version of my VC software I can use with Emacs?

If you are using a graphical revision control tool already, check if it comes with command-line tools. Many such GUI tools are just wrappers for the same command line tools that Emacs requires for its VC integration. Most of the supported VC systems have well supported Free native Windows binaries. For those that don’t Cygwin may be an option. See Other useful ports.

10.4 How do I use the Perl debugger with Emacs?

From Jay Rogers:

Some versions of the perl debugger itself need to be patched to work with emacs. They are perl versions 5.001 and less, and version 5.004_01. To fix, locate and change the code similar to the following code in lib/perl5db.pl

        if (-e "/dev/tty") {
            $console = "/dev/tty";
            $rcfile=".perldb";
        }
        elsif (-e "con") {
            $console = "";                 <---- change "con" to ""
            $rcfile="perldb.ini";
        }
        else {
            $console = "sys\$command";
            $rcfile="perldb.ini";
        }

Doug Campbell also has some suggestions for improving the interaction of perldb and Emacs.

11.1 Cygwin

https://www.cygwin.com/.

Cygwin is a popular complete POSIX emulation environment for Windows. Most of its tools can be used with Emacs, and it covers a wide range of ported software. The main shell used by Cygwin is GNU bash, but other shells are also available. Some Cygwin tools may not interoperate well with Emacs or other native Windows tools, due to the total immersion aspect of Cygwin, including its non-native filesystem mapping.

If you choose to use Cygwin, then its tools will probably be all that you need, but you will need to get image libraries from elsewhere, as the Cygwin ones are not compatible with non-Cygwin software. In fact, if Cygwin is on your PATH when you run Emacs, and Emacs does not find other versions of the image libraries first, then the Cygwin ones can cause problems. Cygwin developers recommend that you do not put Cygwin on your system PATH for this reason. Instead you can make the Cygwin tools available within Emacs by setting exec-path in your init file.

11.2 MinGW-w64 and MSYS2

https://www.msys2.org/

MinGW-w64 is a set of development tools that produce native Windows executables, not dependent on Cygwin’s POSIX emulation DLLs. MinGW-w64 has forked the original MinGW in 2007 in order to provide support for 64 bits and new APIs.

MSYS2 is software distribution and a building platform for Windows. MSYS2 is an independent rewrite of MSYS, based on modern Cygwin and MinGW-w64 with the aim of better interoperability with native Windows software. It plays the same role MSYS does in MinGW. Being a distribution, MSYS2 provides tools to build software as well as more than 2.600 precompiled packages ready for use.

11.3 EZWinPorts

The EZWinPorts project provides many useful ports of recent versions of GNU and Unix software. This includes all the optional libraries used by Emacs (image libraries, libxml2, GnuTLS), RCS, Texinfo, a clone of man command, Grep, xz, bzip2, bsdtar, ID Utils, Findutils, Hunspell, Gawk, GNU Make, Groff, GDB.

11.4 MinGW and MSYS

https://osdn.net/projects/mingw/

MinGW is another set of development tools that produce native Windows executables, not dependent on Cygwin’s POSIX emulation DLLs.

MSYS is a POSIX shell and minimal set of tools that are commonly used in configure scripts. Like Cygwin, this environment uses a non-native filesystem mapping to appear more POSIX like to the scripts that it runs. This is intended to complement the MinGW tools to make it easier to port software to Windows.

11.5 GnuWin32

https://gnuwin32.sourceforge.net/

GnuWin32 provides precompiled native Windows ports of a wide selection of Free software and libraries. Unfortunately, the ports are outdated. Tools available here that are useful for Emacs include:

• Arc - used by archive-mode to edit .arc files.
• Bzip2 - used by Emacs to automatically decompress .bz2 files.
• CompFace - used by gnus to display XFace headers in messages.
• CoreUtils - GNU file, shell and text utilities (also in MSYS)
• DiffUtils - for ediff and producing patches
• FindUtils - for grep-find and other file searches.
• GifLib - library to support GIF images.
• Grep - for searching through files with grep.
• Gzip - used by Emacs to automatically decompress .gz files.
• Jpeg - library to support JPEG images (also in GTK+).
• Lha - used by archive-mode to edit .lzh files.
• LibPng - library to support PNG images (also in GTK+).
• LibTiff - library to support TIFF images (also in GTK+).
• Make - used by compile for building projects (also in MinGW)
• OpenSSL - used by gnus to talk to servers over SSL.
• Patch - used by ediff-patch-file and others to apply patches.
• Tar - used by tar-mode to edit tar files.
• TexInfo - used to build Emacs’ manuals.
• Unzip - used by archive-mode for extracting zip files.
• Xpm - library to support XPM images (bundled with Emacs binaries)
• Zip - used by archive-mode for editing zip files.
• Zlib - required by LibPng (also in GTK+).

11.6 GTK+

GTK+ is a potential source for some of the image libraries that Emacs requires. GTK+ is installed along with other ports of GUI software, such as the GIMP image editor, and Pidgin instant messenger client. If GTK+ is installed when you run addpm, Emacs will use the image libraries that it provides, even if they are not on the PATH. GTK+ ships with JPEG, PNG and TIFF support.

11.7 How do I read man pages?

Man pages for Emacs and other ported programs that you have can be read using Emacs’ built-in manual reader woman. This requires no external programs, but if you do have a port of man, there is also an Emacs wrapper man that which may be slightly faster. A Windows version of man is available from the EZWinPorts site (see EZWinPorts).

12.1 Where can I get more information about Emacs?

If you have general questions about Emacs, the best places to start looking are The GNU Emacs Manual, and the standard Emacs FAQ. In Emacs, you can browse the manual using Info by typing C-h r, and you can view the FAQ by typing C-h C-f. Other resources include:

• The Emacs website
• Other Emacs manuals
• Emacs Wiki

12.2 What mailing lists are there for discussing Emacs on Windows?

The official mailing list for Windows specific help and discussion is help-emacs-windows. See that link for information on how to subscribe or unsubscribe. The list archives are available online.