Cannot attach Database..

I have designed the database in SQL Server Compact and when i try to run the application it showing the following

Code:

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Cannot attach the file 'D:\Webs\Login Page\Login Page\App_Data\UserMaintenance.mdf' as database 'UserMaintenance'.

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Please help me someone...

Do you actually mean SQL Server Express? SQL Server CE uses SDF files and doesn't use a server while SQL Server Express uses MDF files (just like the grown-up SQL Server) and does use a server.

Assuming that it is SQL Server Express, if you connect to that instance in Management Studio, do you see an already attached database named "UserMaintenance"?

its the compact database which is coming along VS2012

I assume that you added the database directly to your project. Did you select a Local Database or a Service-based Database?

Local Database

Then something is really wrong. The Local Database option is for SQL Server CE while the Service-based Database option is for SQL Server Express. As I said, SQL Server CE uses SDF files and no server so the fact that the error message mentions an MDF file and attaching to a server means that you are not doing what you intended to. I think you need to start again.