I made a project on my PC computer, saving it as a tif. I then took it to the Art Institute, editing it on their Apple I wish to tweak it at home but now Ps claims that it is not compatible with this cc version of Ps, where it was originally created! HEL

I made a project on my PC computer, saving it as a tif. I then took it to the Art Institute, editing it on their Apple  I wish to tweak it at home but now Ps claims that it is not compatible with this cc version of Ps, where it was originally created! HELP!!!