registry invalid

so i havent had any issues playing sins in the past in fact i love the game and play the multiplayer like everyday so i got entrenchment. i like it but a friend dosnt have it when i chouldnt get in his games or he in mine i tried to get regular sins back so i uninstalled and reinstalled sins to play a game. i had no issues playing i finished my game and stoped.

later the next day i wanted to play entrenchment however it wouldnt let me install it kept saying somthing like location not found however i chould launch sins from impulse. so i unistalled sins once more and tried to reinstall but now it seys my registration for it is invalid, and i cant even install sins now.

i would like to be able to play and if posible switch from entrenchment to original sins. if i chould get it working again (probly by resolving my socalled invalid registration) i chould probly copy my sins into a difrent folder and play sins from there and update my first sins file to entrenchment so i have both if that wouldnt cause any problems.

so a few questions this may not be the place to ask this but i didnt see a # to call or a suport place on this website.