I haven't tried saving a single record, but I would assume that it would save okay due to it being the only record added. I removed the primary key. The key was a clustered index that is required to be unique. It then saved without a problem. It may be something to do with ADO.Net and how MM is using it. I am planning on just creating another clustered index. I will just make a non-unique index to see if this takes care of the problem.