Reinstalling Prem Elements 12

Had to reinstall from original discs. Now get an error message when rendering. Activate Component. MPEG2. Copy serial number. Follow link, paste, copy unlock code and paste in original pop up.  Trouble is the link is no longer active and gets diverted to Adobe home page. Help desk cannot help and advised I should try the forums for the answer. Or buy the upgrade. I'm only an enthusiastic amateur and really need the upgraded version.