When I double click on an mdf file on Visual Web Developer 2008 (NerdDinner.mdf) it says:
Connections to SQL Server files (*.mdf) require SQL Server Express 2005 to function properly. Please verify the installation of the component or download from the URL: http://go.microsoft.com/fwlink/?LinkId=49251
The URL of course points to SQL Server Express 2008. I have that one installed and running. Any ideas why am I getting that message?