Early last Fall my mother (82, living in Germany) switched to Windows XP. She had some help from a young computerwise person, but things didn't go so well. The programs all functioned, all new drivers were downloaded, but she kept having very frustrating hardware problems: the wireless mouse wouldn't be recognized, same with the scanner. We tried everything, and were just getting ready to buy new accessories, when I noticed that her email had the wrong date. On questioning her she told me that she had to unplug the computer for a little while and that seemed to have changed the date. Hm. My husband suggested to check the computer battery, and that was eventually done, and replaced. Voila, everything works like it's supposed to! The computer was less than 2 years old at the time, so nobody every thought of the battery. With all the systems I have had (all nearly 5 years) I have never had to change the battery, but as you can see: stuff happens. Just thought I'd pass this along.