the error was not occuring when trying to select project. Browsing worked perfectly, i was able to browse and choose my SLN file. the error occurred upon clicking "next". All that aside, installing .NET 4.5 seems to have resolved the issue. 4.5 is not a requirement for vault or for BuildMaster, but seems to have changed something. I found an unrelated artical on google saying that they were getting a MaxArrayLength error, and that the error went away after installing .NET 4.5, so i figured it was worth a shot, and sure enough issue resolved!

Nevermind. I see the answer here ( http://inedo.com/support/questions/820 ). I swear it wasn't there on Friday.

Thanks! I changed the account build master was running under, and it now works.