I have noticed recently, that I am no longer able to view or modify any diagrams on my workstation. I can see the names of the diagrams, but after opening the diagrams, I can't see any of the tables, or even make modifications to them.
If I go to other workstations or the server, using any login (SA, Administrator, NT Auth), I can see and modify the diagrams, just like i used to on my own workstation.
I am, howerver able to create new diagrams and add tables to them. I can then re-open the diagrams and modify them as needed. I have all the latest service packs for SQL Server loaded both on my server and workstation. I also have all the service packs for VS.net and VS6 installed too.