I have had a couple of request from work mates about this.
Something is out there deleting the autoexec.nt file
or Micro$oft have a little "undocumented feature" (as I like to call them)
I found an easy fix on another forum. The admin has stickied his fix
here
I have also found the autoexec.nt file hiding in C : \windows\repair . A quick copy/Paste to C : \windows\system32 and away you go
Happy new year to all
MAx