I have no idea if this works, but you can try% programfiles% / .. / .. / (or something similar) using the location / depth information of the program files folder (or which variable you use) and go to the root (having the right amount of "../") and adding too much from there?
So, to get to C: \ TempData, you might have something like:
% ProgramFiles% / .. / TempData p>
, Windows...
, ...