http://www.imzers.com (formerly http://www.msn-problems.com)
I get a lot of questions from people having problems with MSN Messenger. A lot of questions. MSN-Problems.com turns out to be a very helpful resource with recommendations for each of the various MSN Messenger versions and error codes that people are experiencing. There’s also a very active forum with even more advice from folks very knowledgeable and on-top of current Messenger issues.