VS 2008 Attach to process disabled

I have used the attach to process feature of visual studio a number of time开发者_如何学Gos. However now when i try to attach to a process (dll) the Attach button is disabled. However if i select any other process except the managed one the Attach button is enabled! My problem is closely related to the problem described at the link below

VS attaching to process disabled

A picture of the dialog is attached.

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This is almost certainly because there is already another debugger attached to the process - probably the currently running instance of Visual Studio but it may be another instance of Visual Studio, or another debugger entirely (such as WinDbg or a remote debugging session).

Check the "Processes" window (usually found under Debug -> Windows -> Processes) to see what processes Visual Studio is debugging.

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Found the solution to the problem

How to step into C/C++ DLL from C# application while debugging

http://msdn.microsoft.com/en-us/library/605a12zt%28v=VS.90%29.aspx