Allright, thanks a lot!

Great, it works! i've modified the function call to extern "C" void __cdecl extiteratie( [arguments] ) (from the error messages I noticed the compiler ignores the "__declspec(dllimport)" part when including __cdecl) Also I added an underscore to the function export in the Fortran code which was needed by __cdecl. An alternative is (most likely but not tested) to use __stdcall in the export. I do not think it makes much difference whether I use __stdcall or __cdecl? Thanks a lot! Jan Timmerman

jantimmerman wrote: This does not explain though why it is allowed to say int test; in stdafx.h (which is included also in a lot of places) It's because you're using precompiled headers. VC++ only compiles the header once, and just references it in all the other files that include it. If you turn off precompiled headers, you'll have the same problem there. Ryan "Punctuality is only a virtue for those who aren't smart enough to think of good excuses for being late" John Nichol "Point Of Impact"

Ok, it builds. Only thing that remains is the warning. Thanks for the help!