I don't think you need that pointer to call the function since it's already a pointer, so 326 becomes: retval = (m_PFoo)(infc, infv, exfc, exfv, m_lpDCL, m_lpUserFunctions); Ian Mariano - http://www.ian-space.com/ "We are all wave equations in the information matrix of the universe" - me

I have used those lines of code before, i never had any problem with that, just make sure that the window handle is valide. The World is getting smaller and so are the people.

Well that's your problem then. When mainfunc() terminates, your class will be destroyed, and so will the window. Then your other thread will be calling IsWindow() on a random piece of memory (the HWND has been destroyed, and so now is just a random number), so it will not work. You need to ensure that your class is not destroyed for the lifetime of the other thread. Dave http://www.cloudsofheaven.org

What parameters? Post examples. In general, the client downloads the self-extracting file and then executes it. Kuphryn

Could somebody provide any idea ?

suninwater wrote: It's OK when I "regsvr32 mydll.dll" and it works perfectly. Is this a "debug" version? suninwater wrote: But, the releaseminsize version give me "LoadLibrary(mydll.dll) failed - unspecified error". Does this happen with all "release" versions?

convert my program to a MFC one then convert the MFC one to an ocx. He also told me the first step need only minor change on source and the latter is also not very difficult. Time is so limited though I'm not familiar with VC++... Can you give me some further help? Thank you very much !

Thanks any way. :-)

OK, as your word, I've replace "cut off" with "remove". Sorry. And, can you give me some help ?

I've done this several times and the most effective way has been to convert the DLLs into libraries. First, get a list of all the files in the project (it's not unusual to have some files in the directory which aren't actually in the project.) Second, remove the DllInit function. Usually you don't need to replace it with anything since it doesn't do anything. If it does, you can often create a small private class and instantiate it globally. If that won't work, simply add Init() and DeInit() functions then call them from the main program in the proper manner and sequence. DO NOT get fancy at this point. It's a huge temptation, but one you must resist. Third, fix up the headers. You don't need the "dllimport"/"dllexport", etc stuff. (Nor do you need the .def file.) Add #pragma comment(lib, "put library name here.lib") to the header. Fourth. Ensure the libraries are subprojects of the master project. Add the subprojects to the master. Set the dependencies and paths and you're off! Fifth, oh, and go through the main project to ensure you aren't "manually" loading the DLLs or accessing them through a pointer or other such strangeness.