If you’re having problems with MbUnit, either in its use or in coding against it, the online technical community has produced many blogposts and articles about it which you might want to search through to see if anyone has a problem similar to yours. For example, you might like to try the following searches
If you can't find any help there, please post your queries to one of our Google Groups
Note that both of these groups require you to join the group before you can post a message to the board.
If you believe you've found a bug or an issue in MbUnit, please submit your bug report to us on Google Code. When you do report your bug, please remember to include the following:
Microsoft blogged a nice, easy set of bug reporting best practices a while ago which you might like to read to get a better gist of it.