thanks for your replies. to provide more detail:
i had a project i'd worked on a few years ago, using VC6. i wanted to port it to VC2005, so i imported the vc6 project files and converted them without problems. after fixing minor compilation errors in the source code, i tried to link, and got the infamous KB148652 error (wrong link order for CRT and MFC libraries) in the second (non-MFC) project. the KB article instructed me to force the correct order by creating a file called Forcelib.h, which i did. when i included Forcelib.h in files from my second project that seemed to be causing the link error (i.e., they didn't include Afx.h, even indirectly), i got the following link error:
C:\...\VC\include\new.h(94) : error C2733: second C linkage of overloaded function 'operator new' not allowed<br />
C:\...\VC\include\new.h(93) : see declaration of 'operator new'
i haven't had time to try your suggestion of compiling/linking each project separately; the first needs the second to link, but i have a project that builds the second as a static library into a test program, and will try that.
another strategy i'm in the process of trying is to create two new VS projects (rather than using the imported ones) and adding all the files and changing the project settings to re-create the original projects, but that's going to take a while, they're large projects.
thanks for your suggestions, i'll post back in the next few days as i learn more.