[RESOLVED] Has anybody figured out how to run 2012 apps on XP

Installed 2012 last week and apps won't run on XP or 2003. They give a message "Not a valid Win32 application", or something to that effect. So if I set the platform toolset to Visual Studio 2012 Windows XP, I get a link error "error LNK2019: unresolved external symbol __imp___vsnprintf referenced in function _StringVPrintfWorkerA@20"

I'd rather not go back to 2008, but I'm kind of stuck at this point.