You will need to contact adobe for a crossgrade, but they will require you to to give up the windows version. The boxed version is cross platform and can be used on both platforms. You can try to see if they will take back the download or let you exchange it for the boxed version, but if you've had for a while I'm not sure how much success you will have.
All PSE downloads are single platform, for one of those mysterious adobe reasons.
Yeah I'll do that, I already sent them an email and they won't be back in until after the holiday. I bought it when it can out in September. Ill fight that tooth and nail. That's rediculous!! I'm not trying to chest them. And it's not like its cheap. I don't want to spend another 160.00 just to put it on my Mac. I shouldn't have to!!! That's a lot of money and I should be able to at east have a coue of downloads , that's not right or fair or appropriate.