The last 2 weeks we had some production issues where an unexpected 401 message was returned from our IIS servers. To further investigate the issue, I got an old tool out of the dust; Log Parser Studio . Log Parser Studio is a utility that allows you to search through and create reports from your IIS, Event, EXADB and others types of logs. It builds on top of Log Parser 2.2 and has a full user interface for easy creation and management of related SQL queries. Log Parser Studio allows to query all kinds of log files using a SQL like syntax. It comes out of the box with a large list of sample queries that can help get started. How to use it Open Log Parser Studio(LPS.exe) Click on the New Query button or choose one of the queries from the library A new query window appears Now it is time to first specify the LogType. Click on the Log Type link in the middle and choose the correct type from the list: Next we have to select the files to que...