Okay i just finished wiping out my machine and loading the retail version of Windows 7.
I've been running 7100 on this machine since it came out.
This exe has been my logon script on 7100 for 5 months and has worked perfectly.
Windows is set to run logon scripts synchronously.
I have it configured as my logon and logoff script using different parameters (/Mount & /Dismount).
When logging on windows sits on the "Welcome" screen with the spinning cursor for 12+ seconds.
Then finally it executes the exe.
When logging off the script runs instantly.
If I manually execute the program with the logon parameter the script runs instantly.