Rick
Two items:

1. I certainly can run the C++ client under the debugger. No problem there. I don't see how to run the VFP debugger to view the code of the VFP EXE COM server, set breakpoints, etc. The client creates a link to the server at runtime, at that point, the server is a binary that is registered in the system. The COM server is not a stand alone application, but rather a collection of routines that can be called from a client. I don't see how the VFP debugger can attach to them.

2. I found the cause of my problem. I went back and ran a version of the C++ client that I knew worked, since it existed before I made any changes. It worked today, but even better, it worked with my latest version (the modified version) of the VFP COM server. So, I knew that the bug was in my C++ code that was calling the server. When I looked at the two headers that defined the calling sequence to the COM server procedures, I could see that one of the data type parameters was wrong. Once I fixed that, the whole thing worked again.

Jim

>>Rick
>>Thanks for your suggestion.
>>How do I get a debugger to attach to the server process?
>>Jim
>
>
>Under the Debug menu there's an option "Attach to process". Find your process and attach to it.
>
>It may require some synchronization on behalf of your client if you are instantiating the engine on use. In that case, step through your code in the one debugger (Visual FoxPro debugger, or Visual Studio if your Visual FoxPro code is calling a custom DLL), and then pause at some point and switch to your other debugger which has the COM Server project and source code (compiled in Debug mode) up and running, and attach to the now running server process. Once attached you can set breakpoints, single-step, edit-and-continue, etc.