Help in ASP.NET loginform

Question

I am new to asp.net.
when i  place login control on the form, it auto-generates a databasefile named as "aspnedb.mdf" , then i wana copy all these roles and table from it to my custom db e.g ("inventorydb"), i run the aspnet_regsql file, and attached my shown my correct target database e.g(inventorydb) but when i run the login for it gives me the error
"An attempt to attach an auto-named database for file "c:\dbfiles\inventorydb.mdf".

what to do with this problems,  any concrete solution.

thx in advance