This is a new issue for me, so I'm wondering if anyone else is experiencing the same thing or has any information about the problem. Simply put, Oblivion is being shut down by Data Execution Prevention... despite the fact that Oblivion.exe is in my exceptions list. So I switched DEP to protect system files only. Still shuts down Oblivion occasionally.

This is a rare problem, it doesn't happen under any particular in game circumstances. I notice a slowdown in most instances a matter of seconds before the crash. I'm doubtful the problem is mod related, so I'm going to forego a full modlist and give you some system information instead.

Vista x64 running on an Athlon 64 X2 6000+ 3ghz, 8 gigs of PC 2700 cas2 ram. My Oblivion.exe is 4gb patched. I have MSSE running at all times. Everything Oblivion related that I could think of to be added is already a DEP exception AND MSSE exception. They show properly as exceptions on both lists, it just kills the process anyway and explicitly states Oblivion.exe as the offending executable.

I noticed this right around the time there was a very large Windows Update, mostly security fixes, so I'm wondering if this is something MS did and if other people are having the same problem.

Maybe Oblivion.exe has been infected by a Virus and is calling another part of the Virus when is shut down?

I ran a full gamut of scans with MSSE and Malwarebytes deep scan, and it says I have nothing, and certainly I have no symptoms of any kind of virus. I also specifically checked the Oblivion executable, even replaced and repatched, then checked it after the next DEP shutdown for any change in filesize... it's the same file.

Not that DEP should even be shutting it down even if it was doing something suspicious or infected if it's set up as a DEP exception. Modded Oblivion is known to set off DEP regardless, or maybe only if you have OBSE or something, I'm not sure.

OBSE_Loader.exe is also on my exceptions list, just to clarify. I usually launch it through Bash.