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BackgroundWorker calling COM api method get "Access Violation" error

Posted By:      Posted Date: April 10, 2011    Points: 0   Category :.NET Framework

My WPF appl need to call methods in a COM object (VC++) to do some work. It works perfectly when I call those methods   from the UI thread. As those calls take a very long time to finish, so I decided to move the interaction with COM to a BackgroundWorker. But I got an exception in one COM methods (Other methods still working fine). The error reads:

Unhandled exception at 0x62a7be37 (msvcr100d.dll) in TestApp.exe: 0xC0000005: Access violation writing location 0x0ab0f000.

The signature of the COM method is:


            DWORD size = some func get the size;

            BYTE* pSrcData = the src data address;

            memcpy((void*) pData, pSrcData, size);   //Error occured on this line


    return S_OK;


How the C# calls the method:


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