Road Runner (owned primarily by AOL/TW) will not support XP. From the article: "Road Runner, the second-largest cable Internet service provider (ISP) in the nation with more than 1.4 million subscribers, does not support the controversial new operating system (OS) for its customers and will not support its use on the cable network."" Note that this doesn"t stop customers from connecting to Road Runner from XP systems, but until their staff is trained specifically, Road Runner won"t help them with technical problems arising from that combination.