This error occurs when inheriting a custom automation interface, the following code produces:
__interface i1: idispatch {[ID (1), Helpstring ("Method F1" [IMG] /images/wink.gif [/ img]] HRESULT F1 (void);}; ...... __interface i2: i1 {[ID (1 ), Helpstring ("Method F2" [IMG] / IMAGES/Wink.gif [/ IMG]] HRESULT F2 (Void);}; the above code is automatically created using Visual Studio's "Add method" Wizard. Error reason DISPID DUPID of F1 and F2, Solution:
__interface i2: I1 {[ID (2), Helpstring ("Method F2" [IMG] /images/wink.gif [/ img]] HRESULT F2 (VOID);}; will be manually changed to different values. Reference Information: ATL Digest
