After FX crash at end of Render?

[Tyson Persall]

I am working on a complex project in after effects CS4. When i render final output, the render goes all the way to end but then on the last frame it freezes up and does not complete the file. I have to force CTL+ALT+DEL and restart the machine. The Render window reads as Completed. The file is created on the drive but is unplayable.
The only way i can get the render to finish is if i Restart the computer, start up After effects and then start the render without altering any of the project itself.

I have tried this rendering to 3 different output modules and same result.


System
Intel Corei7
GeForce 285
12GB Ram
Windows Vista 64bit.
Adobe CS4 suite.
850w Corsair Power supply.