An easy way to debug ActiveX EXE Components is to run ActiveX EXE project in the IDE VB environment and then run your client application or client project. But before do that, you have to make sure that your ActiveX EXE project is binary compatible with the respective component exe file that is referenced by your client project. You can set it up in the ActiveX EXE project property dialog box and you always need to do it once in order to keep compatibility.