* Each Win32 process is implemented on top of a separate NT process.
* Each DOS box (ntvdm, NT virtual dos machine) is also implemented on
top of a separate NT process.
* I also believe that each Posix and OS/2 processes uses its own NT
It is true that the entire Win16 system is implemented in one ntvdm, with
shared memory and cooperative (non-preemptive) scheduling within this ntvdm.
Unfortunately this is required since many Win16 apps depend on sharing
memory and cooperative scheduling (especially the latter).
Finally, Win32 (NT), like Unix, allows sharing of memory between cooperating
processes via memory mapping of files.
I'm not sure what happened with your email showing up in a log file. Were
both processes Win16 apps, perhaps?