Most free IIS support forums tend to be dominated by questions related to configuration, how to, setup and so forth. However it's the crash/hang questions that generally do not get answered, or the responses generally tend to be "shot in the dark" suggestions on fixing the issue.

If you have an IIS crash (where a process, e.g. w3wp.exe or dllhost.exe terminates unexpectedly), or a hang (where IIS is not serving pages) then the best way to troubleshoot the problem is through the use of debugging tools. Whilst diagnostic tools like AuthDiag and SSLDiag can help with configuration issue, debugging tools can let you "peek inside" IIS to see what's happening when a crash or hang has occured.

The two most popular IIS debugging tools are adplus.vbs and IISState. Adplus.vbs is available with the Windows Debugging Toolkit. IISState was available with the IIS6 Resource Kit Tools, however an updated version is available for download from To help with configuring and diagnosing IISState logs, I've done up a FAQ page to get you started.