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Cannot get COM interface from properties

Posted By:      Posted Date: August 28, 2010    Points: 0   Category :.NET Framework
My client provides a COM server which exposes some COM interfaces.  The main interface has properties only.  Each property returns a different COM interface. public interface IMain {     ISubIntrf1 Property1 { get; }     ISubIntrf2 Property2 { get; }     ISubIntrf3 Property3 { get; }     etc. } In my C# code, I create an instance with IMain interface:          Type oType = Type.GetTypeFromProgID("Some_Prog_ID");     if (oType != null)     {         Object obj = Activator.CreateInstance(oType);         IMain mainObj = (IMain)obj;         ISubIntrf1 intrf1 = mainObj.Property1;    // <<< Exception is raised at run-time     } {"Unable to cast COM object of type 'System.__ComObject' to interface type 'ISubIntrf1'. This operation failed because the QueryInterface call on the COM component for the interface with IID '{5562B6FF-E01F-4AE1-A080-DF5E4157E3C4}' failed due to the following error: No such interface supported (Exception from HRESULT: 0x80004002 (E_NOINTERFACE))."}    System.InvalidCastException I know the COM registration is good and the COM server is running fi

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