[AccessD] Puzzling problem with querying

[FW Salato Center]

They were working fine before...? 

Susan H. 

Running Access 2007. When trying to open an existing query (almost all of them), or create a new one, I keep getting an error message that reads,

   '' is not a valid name. Make sure that it does not include invalid characters or punctuation and that it is not too long.

When I look at the SQL view of a query, it all looks correct, and in fact runs correctly as well. Any idea what might be causing this error message to appear?