If you add another project, a solution will appear, so if you only see one project in the solution, but if more than one project is connected to the same solution, you will see the solution.
You can add a new project from the File menu, then select Add to Solution.
And I think this problem is solved using SP1.
Update:
Although my answer explains why this is happening, but I believe that the correct solution is https://stackoverflow.com/a/312977/
Amr elgarhy
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