Cannot open class repository tree

Testing SED for Visual Studio .NET 2003.

I have classed in Code, and I am trying to general a Class diagram from the code; however…

I cannot open the class repository tree. I select it from View -> SDE-VS Windows -> Class Repository Tree, but nothing happens.

When I try any of the views, none work except Diagram Tree, which it switches the tabs to view the tree (unless I close the Diagram Tree, then I cannot get it open unless I restart VS)

Has anyone else run into this problem, if so… any solutions?