Help with Running Rome: Total War and EB

[MRC_Revenant]

I have been struggling with this all night and I was hoping that someone might be able to give me some guidance. A while ago, I installed EB and was pretty successful playing it. However, tonight, I was no longer able to play EB. Everytime I try to open it, I get the message, "Access denied, please login with administrator privileges and try again." When I try to run the game in Admin mode, it does not load. The same thing is happening to the original Rome: Total War. I have tried re-installing both Rome and EB, in different locations, but I am still unable to play. I either keep getting the Access Denied message, or the game does not load if run in Admin mode. At this point, I do not know what else to do, as I have tried everything I could find, including:

*Enabling Admin mode (game does not run)
*Setting compatibility with Windows XP (game does not run)
*Installing the game in C:\Users\xxx (still getting admin error)
*Disabling UAC (still getting admin error)

I am running Windows 8.1 (yeah, I know); however, my second PC has Windows 7, and I keep getting the same set of errors.

Does anyone have any ideas on what I can possibly do to fix this? It would be very unfortunate if I can no longer play this game. :(

Thank you in advance for your help!

EDIT: I found it weird that every time I reinstalled Rome, it did not prompt me for a CD Key.