Enabling Failed Request Tracing
Occasionally I get questions on how to troubleshoot intermittent issues in IIS. One example is an intermittent 500 status code and another example is a slow page load. In IIS7 and later there is a simple module that you can install as part of IIS called Failed Request Tracing (FREB).
Using Failed Request Tracing you can easily configure it to log the worker process information when a specific status code is generated, a page takes longer than X seconds to load, or if an event viewer entry is generated. You can then review the compiled data after the fact to help track down the root cause of your issue.
Here is a good post on how to enable Failed Request Tracing:
Rick is a Senior Support Lead at OrcsWeb, a hosted server company providing managed hosting solutions.