Different develope OS problem using VC++6?

[alexw]

Hi, I meet a problem after I move my project from
the Win98 + VC++6 to Win2K + VC++6, the code of
serial communication doesn't work! I put the serial
comm code into a seperate dll just used the SDK API,
and the main program is used MFC. If I take the release
version of dll be compiled under Win98, that's work,
but debug version doesn't. And both version of compiled
under Win2K not work either.
Does anyone has been met this kind of problem and know what's wrong of it?

Thanks.

Alex Wu