I have created a "COM interop" enabled DLL and TLB file in VB.net 2005 and used it in PowerPoint as a reference and it worked fine on the development machine. But on target machine which have .net framework 2.0 it did not worked. I opened the PowerPoint 2007 with security level LOW, and it showed me MISSING reference of the DLL. When I tried to add DLL file it showed me an error "Can't add reference to specif file". I was able to add the .TLB file as a reference and see the list of available functions in it. But when I executed the program it showed me "Automation Error".
<ComClass(Core.ClassId, Core.InterfaceId, Core.EventsId)> _
Public Class Core