Help please with re-installing PhotoshopCS6 from purchased CD

I received a message when I last attempted to open Photoshop CS6. It was from Adobe and requested me to uninstall Photoshop CS6 and then to re-install it. I am unable to do so - the message informs that errors are encountered. I had a chat online with Adobe and was instructed to dowload a new update for Adobe Appliacation Manager which I have done. I have restarted the computer but still receive error messages when attempting to install from my purchased CD.

From the outset of the purchase about one year ago I have had issues with the registration. On another Adobe online forum, Jeff A Wright, an Adobe staff member, provided a temporary fix that has progressed no further despite requests online to him.

I use Photoshop CS6 in real time combined with Powerpoint to teach photography in a university setting and really need to be able to utilize the program that I purchased.

Please assist me in getting it back.

Thanks for any assistance. Stan