How I do that?
I don't want to sound like a smartass, but your signature shows you've got like a half-dozen very souped-up Amiga's. You don't know how to edit your startup sequence?
Just put "echo 1" "echo 2" "echo 3" between each line of your startup sequence. It will print the number on the screen as it's executing. Count whichever line it gets to. When it stops, you've found your culprit.
There is also a much easier way to do this automatically, but %#%) if I can remember what it is. Google?