Q. Every time that I start my PC, which runs with Windows XP, I have to reset the date and time. Why?

A. PCs and laptops contain a usually coin-sized rechargable battery that enables the PC to remember, inter alia, the date and time when your PC is turned off or there is a powercut. Typically, these batteries last about five years before needing to be replaced, and I imagine that your onboard battery has reached the end of its life. With a PC, it is simple to change it oneself. Unplug the mains cable - important! - and then open the PC's casing. The battery is likely to be visible on the motherboard (the main circuit board). Remove it (noting which way up it was!) and take it to an electrical retailer and buy a replacement. If you don't fancy doing it yourself, can't see the battery, or use a laptop, then take it to any PC maintenance shop and they will do it for you. It shouldn't be an expensive job!