Operator Tool doesn't work

[Milanor]

When I try to restore "Operator Tool", this window appears:

http://i76.servimg.com/u/f76/13/06/18/30/aide_b10.jpg

and...

TITLE: Microsoft SQL Server Management Studio
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Restore failed for Server 'CLADFIRE\SQLEXPRESS'.  (Microsoft.SqlServer.SmoExtended)

For help, click: http://go.microsoft.com/fwlink?ProdName=Microsoft+SQL+Server&ProdVer=10.50.1600.1+((KJ_RTM).100402-1540+)&EvtSrc=Microsoft.SqlServer.Management.Smo.ExceptionTemplates.FailedOperationExceptionText&EvtID=Restore+Server&LinkId=20476

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ADDITIONAL INFORMATION:

System.Data.SqlClient.SqlError: The operating system returned the error '5(Accès refusé.)' while attempting 'RestoreContainer::ValidateTargetForCreation' on 'C:\Program Files\Microsoft SQL Server\MSSQL10.SQLEXPRESS\MSSQL\DATA\OperatorTool.mdf'. (Microsoft.SqlServer.Smo)

For help, click: http://go.microsoft.com/fwlink?ProdName=Microsoft+SQL+Server&ProdVer=10.50.1600.1+((KJ_RTM).100402-1540+)&LinkId=20476

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BUTTONS:

OK
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Someone can answer me? Please!

[MentaL]