Deinstalling and reinstalling CS5

Before you prcoeed you should know that you can have it installed and activated on two machines.  You do not have to uninstall if you would like to have a backup installation available.    

First open the program on the old machine and go to Help -> Deactivate.  If you still want to uninstall at that point do so as you would for any application on a Mac... but you do not have to uninstall if you don't want to because the program is effectively disabled on the old machine at this point.

Then install the program on the new machine the same way you installed it originally.  If you need to download it, check your Adobe account online to see if there is a download link there for it.  There is a resource where you can download the trial version and activate it using your serial number.

Be sure to follow the steps outlined in the Note: Very Important Instructions section on the download pages at this site and have cookies enabled in your browser or else the download will not work properly.

CS5: http://prodesigntools.com/all-adobe-cs5-direct-download-links.html