SQL 2005 express query

I have reinstalled a server with OS 2008 R2, and SQL 2005 Express, now I am able to create or delete databases.. I have full admin rights. Then, I installed and attached the Adventure works DB.. after that, I wanted to play with queries, so I did run a couple of queries successfully to the person table of Adventure works. After that, and without having done anything in between.. I have not been able to run any other query.. it gives me these errors: If I go to the table and say "script table as", select to a "new query editor window", I get this: 'The directory name is invalid. (mscorlib)"   If I select to Clipboard and paste in a query, and execute, I get this: "An error occurred while executing batch. Error message is: the directory name is invalid   The machine has plenty of room since it is only running this for me. I have resta ...