Config.sys and Autoexec.bat
Most access control programs provide a function that make it
impossible to interrupt the computer's boot process.
This is one of the fundamental features of a security
system, but the function can easily lock up the computer if you do not do
things in the correct order. When updating autoexec.bat or config.sys,
you should always should always check that the
function is disabled before restarting the computer. The function is
disabled in different ways depending on the system. The most common method
is to insert 'REM' in front of the line ‘switches /n /f’ in config.sys.
This allows you to use F5 or F8 in DOS 6.x to
interrupt the boot process.
Windows Privacy Tools - http//www.privacywindows.com