I have a problem adding diagrams in my database.
I add the tables, save the diagram but when I try to edit it SQL SERVER
Enterprise Manager shows me the following message:
"[MS Design Tools] - The Database Object no longer exists."
PS - If I refresh the diagrams, it disappears of the screen. But if I try to
save another diagram with the same name, the Sql Server alert me that there
is a diagram with the same name, and ask me if I want to replace it.
The owner of the database is sa and I'm acessing with all permissions set.
Can somebody help me with this problem?

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