VS2008 and SQL Express 2008
3 answers
If you add MDF to your website folder, I think you are using the Custom Instances feature . It is hardly advisable, and would be corrupted :
This feature will be removed in a future version of Microsoft SQL Server. Avoid using this feature in new designs and plan to change applications that currently use this feature.
Instead of using custom instances, use Server Explorer to connect to Sql Server Express and create a database there.
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