Desperate.... IL2 quit working...

[Spinnetti]

Background:
Been flying Il2 since the demo, on multiple machines and configs. Currently a quad core i7, 4gigs ram, ATI 4850 video. Plays the game maxxed out very nicely (or did) on XP SP3

Current Situation:
I tried to do a clean install of Win 7 which was a disaster. I eventually got IL2 to install but not run. Trackir1 won't work under win 7 either, so I gave up. I did a reformat, and reload of XP, and applied all the latest patches. I loaded IL2 off the disk, but it WILL NOT RUN. I have NO idea why and can't figure it out. I've reloaded this thing dozens of times without any problems. It starts to go, then in the task manager it just disappears. I didn't try patching up to 4.09m, but I'll try that next.

Any ideas? This is driving me nuts.