Problems Copying ASPNETDB.MDF to a new web site

Hi,

We have a web site deployed on a server (which is actually running XP sp2) which uses aspnetdb.mdf in conjunction with an asp.net Login control to handle logins. Call it Site1. Works great. We copied the web site to a dev machine, made some modifications, and xcopied it back to a new virtual directory on the server - call it Site2. Once we verify that Site2 works correctly, it will supercede Site1. Site2 needs to inherit the exact same security db as Site1, so we copied the aspnetdb.mdf files from the App_Data folder in Site1 over to Site2, overwriting the original files in Site2 (which themselves had originally been copied from Site1). Now Site2 will not allow any logins - it says the username/password is not found.

 Any ideas why this might be happening?

Thanks.

Dan
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