IConnectionPoint::Advise call returned E_NOTIMPL

Question

Note:

• No MFC
• No ATL
• Using Visual C++

While attempting a connection between the connection point and the caller's sink, an E_NOTIMPL (0x80004001) was returned.

Illustrated below:

hresult = pConnection->Advise(
                             pSinkUnk,
                             &dwAdvise);

Question:

• How did this occur?

Regards

Answer 1

That sounds to me like the connection and/or the object that you want the events of doesn't implement the events interface that you are expecting. If that's your object, maybe verify that your QueryInterface() returns an instance of your object for that interface?

Answer 2

According to MSDN, it states that connection points that only allow one connection can return E_NOTIMPL from its EnumConnections() method. Would it be possible that a connection has already been made for this connection point? Maybe this particular implementation returns E_NOTIMPL from Advise() in this case as well?