Cannot Attach Database to SQL Server Management Studio 2008 R2 I installed SQL Server 2008 R2 just now and wanted to attach my previous databases. Attaching a Database gives an error.


  Attached is the image of the error.




Any Suggestions and help will be appreciated. :)
Regards.
Something seems not quite right with your question.

SQL 2008 is version 655
SQL 2008R2 is version 661

I would expect that you would only see that error if you are attempting to attach a 2008R2 DB to 2008, not vice versa. 

As soon as you attach a DB to 2008 R2, the version is changed to 661 and can no longer be attached to a 2008 server.