you can write out a simple one at the prompt that is there when you boot.
copy con autoexec.bat
The copy con autoexec.bat starts the creation, and ^z finishes. The ^z is an end of file mark, get it by using cntrl-z or press f6 key.
But check to see if you have an autoexec.bak and config.bak, or .000 .001 etc
There is no reason for any individual to have a computer in his home.
President, Digital Equipment, 1977