Itunes cant find folder %APPDATA%\

I had a problem with my computer when backing up the harddrive. It had to clean out some stuff and it ended up cleaning out Quicktime and it told me to uninstall intunes and reinstall it. i went onto apple.com and tried reinstalling it but it popped up that itunes couldnt find folder %APPLDATA%\ so i installed Quicktime with no problem and tried downloading itunes but it popped up again.

HELP PLEASE!!!!!!