Cannot register Adobe CS5

I just purchased a MBP with Adobe CS5 on it; the seller said he used a seller's license, so it was as of yet un-registered. He told me to register it with my Adobe ID so that I could regain the software if anything ever happened to my computer. Whenever I try to register it, though, Adobe tells me it cannot register, and I should try again later. I can't get the Apple software to register on their sites, either. Am I doing something wrong? What gives?