Problem with copying project

 hello,
 I have a project created where I use membership. I want to have a security copy of the project, so I just copy it and create a new one. But when I execute it I get an error of aspnetbd.mdf saying that thereÃ?´s another database with equal name and that this database is in a network path not allowed for databases files.
How can fix the error?
Thanks in advanced
 
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