I am (trying to) use Embedded Visual C++ 4.0 on Parallels for Windows. The host is a Pentium XP SP2 machine, the guest is XP SP2 as well. When EVC4 tries to access the WInCE emulator (VPCAppSv.sys is a part of this), the guest blue screens with a page fault. VPCAppSv.sys is officially known by Microsoft to cause problems with XP SP2 "running in PAE or NX mode". Because of that, XP SP2 disables VPCAppSv.sys in that case. But that's apparently not what is happening, as VPCAppSv.sys IS enabled and crashes when used. VPCAppSv.sys is obviously weird low level stuff, and it's doing emulation tricks itself, so I'm not too astonished (but unhappy) that it fails within a VM. My first guess is that Parallels runs the guest in some mode that causes similar problems to VPCAppSv.sys as PAE or NX do, but such that XP SP2 does not detect it as such and therefore does not disable it. At this time I'm testing with Parallels Win only because my Intel Mac is not yet here - as soon as it is I'll switch to Parallels Mac (already purchased). However now I'm a bit worried that I'll have the same problem with VPCAppSv.sys in Parallels Mac. I hope it'll behave different, as not having EVC4 emulated would be a show stopper for my virtualisation plans. Any more info on this or experience running the WinCE emulator on Parallels?