Editing AUTOEXEC.BAT (section)

==Usage==
<code>AUTOEXEC.BAT</code> is read upon startup by all versions of DOS, including MS-DOS version 7.x as used in [[Windows 95]] and [[Windows 98]]. [[Windows Me]] only parses environment variables as part of its attempts to reduce legacy dependencies,<ref name="Microsoft_288997"/> but this can be worked around.<ref name="Multiboot"/>

The filename was also used by {{Interlanguage link|Disk Control Program|de}} (DCP), an MS-DOS derivative by the former East-German [[VEB Robotron]].<ref name="DCP_2016"/>

In Korean editions of MS-DOS/PC&nbsp;DOS version 4.01 and higher (except for PC&nbsp;DOS 7 and 2000), if the current country code is set to 82 (for Korea) and no <code>/P:filename</code> is given and no default <code>AUTOEXEC.BAT</code> is found, <code>[[COMMAND.COM]]</code> will look for a file named <code>KAUTOEXE.BAT</code> instead in order to ensure that the [[DBCS]] frontend drivers will be loaded even without properly set up <code>CONFIG.SYS</code> and <code>AUTOEXEC.BAT</code> files.<ref name="Paul_2001_KAUTOEXE.BAT"/>

Under DOS, the file is executed by the primary copy of the command-line processor (typically <code>COMMAND.COM</code>) once the operating system has booted and the <code>[[CONFIG.SYS]]</code> file processing has finished. While DOS by itself provides no means to pass [[batch file parameter]]s to <code>COMMAND.COM</code> for <code>AUTOEXEC.BAT</code> processing, the alternative command-line processor [[4DOS]] supports a <code>4DOS.INI</code> ''<code>AutoExecParams</code>'' directive and <code>//AutoExecParams=</code> startup option to define such parameters.<ref name="4DOS_8.00_HELP"/> Under [[Concurrent DOS]], [[Multiuser DOS]] and [[REAL/32]], three initial parameters will be passed to either the corresponding <code>STARTxxy.BAT</code> (if it exists) or the generic <code>AUTOEXEC.BAT</code> startup file, <code>%1</code> holds the virtual console number,<ref name="DigitalResearch_1989_PrinterSpool"/> <code>%2</code> the 2-digit <!-- PC -->terminal number (xx) (with 00 being the main console) and <code>%3</code> the 1-digit session<!-- relative virtual console --> number (y).<ref name="Novell_1993_FYI.M.1901"/>

[[Windows NT]] and its descendants [[Windows XP]] and [[Windows Vista]] parse <code>AUTOEXEC.BAT</code> when a user logs on. As with Windows Me, anything other than setting environment variables is ignored.<ref name="Microsoft_124551"/> Unlike <code>CONFIG.SYS</code>, the commands in <code>AUTOEXEC.BAT</code> can be entered at the interactive [[command line interpreter]]. They are just standard commands that the computer operator wants to be executed automatically whenever the computer is started, and can include other batch files.

<code>AUTOEXEC.BAT</code> is most often used to set [[environment variable]]s such as keyboard, soundcard, printer, and temporary file locations. It is also used to initiate low level system utilities, such as the following:

* [[Virus scanner]]s
* Disk caching software
* Mouse drivers
* Keyboard drivers
* CD drivers
* Miscellaneous other drivers