Log4net is a great tool for logging in a .NET application and everything is well documented. Finding what you need can be a pain though. If you checkout the configuration manual, you read about all the appenders and a little about the pattern of the message that is logged. You can set that pattern if you want. What they fail to provide however is a reference of the tokens you can use in a pattern (for instance %exception). They only show a sort of default pattern. After digging for about 10 minutes, I finally found the list within the SDK reference. It would be great it someone were to add I direct link to there from the configuration manual.