Where should program data files be installed (Windows 7 64 bit) so that a standard user can acess (read, modify, etc.) them?

Back in (good old ) XP days, I placed executables and data files in C:\Program Files\My App. But under Win 7, these can't be accessed by a standard user. In Win 7 (64 b), I've tried placing them in C:\Program Files (x86)\Common Files\My App, but this permits access by an Administator, not a Std User. So that is no good? Any suggestions? (or helpful tutorials from you to me )

halw