SQL Server 2008 Express failed to attach mdf file

Question

Here is the message. What\'s wrong with it? Is it a installtion problem?

TITLE: Microsoft SQL Server Management Studio

Cannot show requested dialog.

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Answer 1

I prefer Windows authentication, and had the same error with SQL Server Standard Edition because my Windows authentication login didn't have enough privileges ( was only 'public' role ) . So logging as "sa" and adding "sysadmin" role for my Windows account login solved the problem.