Ok so my iMac is about 2 years old. It has a 500gb HD, with 250gb free. I installed The Sims 2 on this thing when i first got it, played it with no problems, then stopped for a while. I was bored tonight, put the CD in to play it again, but when I try and open the application it says:

"The Sims 2 requires at least 1 MB of free disk space. Free up some space on your local disk and then re-launch The Sims 2."

This makes no sense to me and I can't get it to work. Any help is appreciated.