System restore

Sometimes your computer crashes for no easily determined reason. You may have been invaded by a nasty virus, or it may be an incompatibly between two bits of software, it may be that there was bad conjunction between Jupiter and Mars. One resort is to employ the System Restore capabilities of XP or Vista. (To access it, on XP at least, go to the Start menu, and choose Help and Support. You'll find System Restore under the Pick a Task options.) It's pretty self-explanatory to use, and in theory it will restore your system to a date and time you choose (eg, before you installed that last bit of suspect software), without changing any of your data, as in your working documents. This article at PC World tells you more. Be aware, though, that System Restore is not perfect, and I have even heard of instances where it so corrupted the Registry that a complete reinstall of the operating system was necessary. In its defence, I have to say that it has saved my bacon on several occasions, and so far I have had no problems with it. To be safe, it is recommended you back up all important files before you do a restore.