I have a database diagram for my database, but when I open it in SQL Server, I almost immediately get a message saying some permissions changed or tables in the diagram were dropped or renamed, and tables in the diagram vanish before I can even scroll over to see what or where they were.

Basically, it's saying, "Hey, you know all that time you spent laying out tables in this diagram... half of them are going to vanish when you view it, and I'm not going to tell you which tables vanished or where they were in the diagram. You're just going to see a bunch of random empty spaces where tables used to be ;)" Ridiculous.

So I thought that maybe if I look in the dbo.sysdiagrams table, I could look at some plain text definition of the diagram to get a clue about the names of the tables that went missing (because thier names were probably only changed slightly) or their coordinates in the diagram (because their spatial location would give me a clue as to what they were), so that I could re-add them, but I can't, because it's a binary definition.

So, is there some other program I could use to view the existing database diagram that's not going to just drop and forget the missing tables without telling me what they were, or is this information lost and at the mercy of some SSMS-proprietary database diagram format and viewer which refuses to cooperate with me.