Folks, I knew it would work, but just in case it's of interest I can report that a parent Any CPU process can start a child x86 process which can Interop with native 32-bit DLLs.
I opened a mini WCF server with TCP binding in the child and a corresponding WCF client in the parent. Then the parent and child can talk to each other and the parent can (indirectly) pull data back from the C++ DLL down in the child process. This creates really good isolation, as the child process and the native stuff is all pushed off into its own folder and doesn't pollute the caller. You can see the Process parent-child relationship in procexp. You've got to set all the ProcessStartInfo<http://msdn.microsoft.com/en-us/library/vstudio/system.diagnostics.processstartinfo.processstartinfo(v=vs.100).aspx>values correctly for your needs, set EnableRaisingEvents<http://msdn.microsoft.com/en-us/library/vstudio/system.diagnostics.process.enableraisingevents(v=vs.100).aspx>= true and listen to the Exited<http://msdn.microsoft.com/en-us/library/vstudio/system.diagnostics.process.exited(v=vs.100).aspx>exit to know if the child actually exits when you request it to. The parent can exit and the child keeps running (like foreground Threads do). It's up to you to negotiate the lifetimes of the parent and child correctly. Greg K
