I was looking over net, and found that many people report OOM errors with Windows7, so it seems it's more OS issue than software. Maybe You should try contacting Microsoft Support?So what I found over net: try running fsx with just one memory stick, or try using two in one channel configuration, also updating bios won't hurt.

No, operating systems needs paging file, whatever amount of ram You have installed. It can run without it flawlessly for weeks, and all of the sudden generate OOM error.

Mine has been running not for weeks but for years with no paging file. It does not require one with such large memory installed. Without the paging file it frees disk space (not a concern these days with cheap drives), and speeds things up as it does not need to swap stuff in and out. Sure if you have a paging file it will get used but if you don't it wont.

But if i contact Microsoft i have to Pay very much......