I'm calling some code from a third-party dll (an interface to an add-in from a partner company that we work with) from my own powerpoint add-in.
They have provided a sample solution where the following code works as expected.
Microsoft.Office.Core.COMAddIn thirdPartyAddin= app.COMAddIns.Item("thirdPartyAddin");
IthirdPartyService x =thirdPartyServiceFactory.GetThirdPartyService(thirdPartyAddin.Object);
I am trying to use the same code and call it inside my plug-in.
What is happening is that I bind to a thirdPartyAdd-in just fine. However, when I call the second line, to get the the interface to the thirdparty service, I get the following exception:
"Unable to cast transparent proxy to type IthirdPartyService" .
What could possibly be the issue? I think I've searched through every single google-generated topic on this issue, an nothing helped.
Thank you in advance