Windows: AUTOEXEC.BAT Is Not Run During Boot (71522)


The information in this article applies to:

  • Microsoft Windows 3.0
  • Microsoft Windows 3.1
  • Microsoft Windows 3.11
This article was previously published under Q71522

SUMMARY

The AUTOEXEC.BAT file is not run when you boot your computer if the "SHELL=COMMAND.COM" statement in the CONFIG.SYS file is missing the "/P" parameter.

MORE INFORMATION

The "SHELL=" statement tells the system what command processor to load during boot up. Most often this is used to load the MS-DOS COMMAND.COM to increase the environment space. The correct syntax for this is: 
SHELL=C:\DOS\COMMAND.COM /E:512 /P
In the example above, the "/E:" parameter is increasing the MS-DOS environment to 512 bytes (the default is 160 bytes).

The "/P" parameter tells COMMAND.COM that this instance of itself is permanent. Without this parameter, COMMAND.COM would load itself into memory, then terminate that instance of itself. In doing so, the process of running the AUTOEXEC.BAT file is skipped.

REFERENCES

"The MS-DOS Encyclopedia," pages 782-783. Microsoft Press, 1988.

"Supercharging MS-DOS," pages 106-115. Microsoft Press, 1989.
Modification Type:MinorLast Reviewed:7/7/2005
Keywords:KB71522
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