1) Write a exe program that uses your COM.
2) Launch the exe.
3) Open your COM Project is Visual Studio
4) Attach the already running exe with the Project.
5) Keep the break points and start debugging it.
see am not able to understand the 4th step.
attach in the sense by changing the configuration properties in that debugging and then
command and passing the path of the exe. if this the way then its control not coming to break point or i may be wrong to the exe ....