Windows ME only parses environment variables as part of its attempts to reduce legacy dependencies,[1] but this can be worked around.
[2] The filename was also used by Disk Control Program [de] (DCP), an MS-DOS derivative by the former East-German VEB Robotron.
[3] In Korean versions of MS-DOS/PC DOS 4.01 and higher (except for PC DOS 7 and 2000), if the current country code is set to 82 (for Korea) and no /P:filename is given and no default AUTOEXEC.BAT is found, COMMAND.COM will look for a file named KAUTOEXE.BAT instead in order to ensure that the DBCS frontend drivers will be loaded even without properly set up CONFIG.SYS and AUTOEXEC.BAT files.
It is also used to initiate low level system utilities, such as the following: In early versions of DOS, AUTOEXEC.BAT was by default very simple.
The DATE and TIME commands were necessary as early PC and XT class machines did not have a battery backed-up real-time clock as default.
The following is a basic DOS 5 type AUTOEXEC.BAT configuration, consisting only of essential commands: This configuration sets common environment variables, loads a disk cache, places common directories into the default PATH, and initializes the DOS mouse / keyboard drivers.
The file is not used during the operating system boot process; it is executed when the MS-DOS environment is started, which occurs when a DOS application is loaded.
Windows only considers the SET and PATH statements which it contains, in order to define environment variables global to all users.
The Tweak UI applet from the Microsoft PowerToys collection allows to control this feature (Parse AUTOEXEC.BAT at logon).