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sql mdf file attach error

Last Modified: 2012-05-10
I have a set of mdf and ldf files given to me by a client. I open sql server express management studio and try to attach the mdf files as a database. I recieve an error "Unable to open physical file blah\blah\blah operating system error 5: (access is denied) (Microsoft SQL Error: 5120)

The file is not open in any other program, and all permissions are applied to the file.

Why would this be happening, how to fix?

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In administrative tools > services > try to run the MSSQL service under local system account it should work.

Use the below script to find the sql service account


Code Snippet

declare @sqlser varchar(20)

EXEC master..xp_regread @rootkey='HKEY_LOCAL_MACHINE', @key='SYSTEM\CurrentControlSet\Services\MSSQLSERVER',

@value_name='objectname', @value=@sqlser OUTPUT

PRINT 'Account Starting SQL Server Service:' +convert(varchar(30),@sqlser)



After getting the service account try the below steps to provide privilege


      Right click on the folder C:\ArrowSQL\Arr@Data and click on properties
      Click on security tab
      Click on Add button and add sql service account
      Provide modify privilege and click ok
      Verify both mdf and ldf have modify privilege
      Attach the db!

or  Refer  http://social.msdn.microsoft.com/Forums/en-US/sqldatabaseengine/thread/9e563890-e35f-4524-82b9-3cca08fec5ed
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you may need to check whether you have already got same database running.

when you re-attach, just open the options tab to see the path is correct or not, maybe the Drive letter need to be changed.


mdf AND ldf solved it.
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