Client calls to Active EXE, strange behaviors

Hello, some VB books states that in order for a client app to reference an Active EXE class, Active EXE has to be running. But I found it to be contrarary. What I did was to open Active EXE server in one VB session, open the client in another VB session. Hit the run button on the client app, it makes the correct calls to the ActiveX EXE server no problem. However, if I start to run the ActiveX EXE in its VB environment first, and then try to run the Client app an error occurs. ("error code 430: interface not supported"). ??? Strange.

ActiveX EXEs do not have to be running in order for classes to be made from them. They simply have to be referenced from the calling project. Things like Word and Excel need to be running, because they are registered in the Wnidows ROT, which allows objects to be created dynamically. When you're trying to create classes from within the VB IDE, you will get the error because of the VB IDE. Compile both EXE and all will come out fine.