Download and run the cleanup tool to remove traces of the failed attempt: CS Cleaner Tool for installation problems | CCM, CS6, CS5.5, CS5, CS4, CS3
Are you working from a disk, or from a download? You can download the installer again from Download Adobe CS5.5 Trials: Direct Links (no Assistant or Manager) | ProDesignTools if you need to be sure there is no damage to the installer. Read and follow the directions on the page very carefully or the download will not be available. Don't forget to decompress it before running.
I am working from Disc. I will be trying again tomorrow. I appreciate your help. I will let you know if worked/