Nvappfilter was now my primary suspect, but I didnâ€™t have direct evidence that it was responsible. I continued to use the system and followed the same debugging steps on the next several crashes. Whether it was IE, WMP or a game, the faulting stack was always the same, with Nvappfilter calling HeapFree. Thatâ€™s still not conclusive proof, but the anecdotal evidence was pretty compelling.
At that point I went to see if there were updates for Nvappfilter, but I wasnâ€™t sure what software package it was associated with. I entered its name in a Web search and discovered that itâ€™s part of the nVidiaâ€™s FirstPacket feature that prioritizes game traffic and thatâ€™s included in the nForce motherboardâ€™s software:
I went to nVidiaâ€™s site and downloaded the most recent nForce driver package, but it failed to update Nvappfilter.dll and I continued to have the crashes.
The nVidia control panel offers no way that I could find to prevent Nvappfilter from loading, so my only recourse was to manually disable it. I wasnâ€™t using the FirstPacket feature, which I had previously been unaware of, so I wouldnâ€™t miss it, but first I had to figure out how it configured Windows to load it. For that I turned to Autoruns, where I found references to Nvappfilterâ€™s 32-bit and 64-bit versions in the Winsock Layered Service Provider (LSP) section:
I deleted all of Nvappfilterâ€™s entries, rebooted the system and have been crash-free since. While I was writing this post, I checked again for nForce software updates to see if Nvappfilter had been updated. The latest version doesnâ€™t look like it includes Nvappfilter or any other Winsock LSP, so assuming Nvappfilter was at fault, itâ€™s no longer an issue.
Not sure if this should have been posted here or not. But I found it a good read to explain why nVidia crushes with Vista.