error:failed retrieve data for this request

I need to attach my database to SQL server 2008(I used it before without problem),but now when I want to attach db , sqlsrv sent me this error.

error:failed retrieve data for this request.开发者_高级运维

Why do I have this problem and how can I solve it?

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Please make sure that the SQL Server Service account has modify permissions over the physical mdf and ldf file on the hard drive that you are trying to attach to a SQL Server instance, and modify permissions also over the folder that contains the file