When we left off on this issue, the app pool was crashing at semi-random intervals. After much discussion with Microsoft’s IIS forum, Microsoft’s ASP.Net forum (not much help there), and peer development groups (AZGroups.com primarily), I downloaded and installed IISState.exe, which is a command line monitor (basically) that is placed on the IIS server and listens for app pool issues. It’s far more detailed than Event Log or App Pool logging, providing codes at every POST/GET. Additionally, I tried turning app pool recycling completely off with no success, and also tried scheduling a single recycle in the middle of the night, also without success.

I decided to run IISState and see what happened. Upon running I noticed the expected logging, with typical “Ok, that worked” codes being thrown. After almost 2 days of running fine, the app pool finally crashed and IISState captured it. The interesting thing is, the error code it threw was a “C++ EH exception – code e06d7363 (first chance)”. Initial research shows this to be a problem internal to IIS. So far, additional research proves this is either not well known or not well documented. I also researched a forum about the error, and their recommendation was to uninstall and reinstall IIS. Yeah…..not happening. In fact, that solution is insulting. Similar to when your computer is slow, blow away the hard drive and reinstall the OS. Please, I thought we were professionals here!

So, the issue remains unresolved at this time. I had to put it aside temporarily to work on other projects, but it’s very much a priority to discover root cause and resolution. As soon as I get to that point, or if I discover anything else I’ll post it here.