Do you have some nagging computer problems? Then try this site from Microsft before trying anything else. Just visit this site at http://www.microsoft.com/athome/troubleshoot101.aspx#fbid=jhLNj6qvPIo and try to find some solution first. The subject is explained in a simple and very neat way. See this example
If you’re encountering a different kind of obstacle – your new device won’t appear on your desktop, an application you added won’t run, you see an error message, or your computer is refusing to start up – here are a few preliminary steps:
Before adding any major hardware or software to your system, make sure you've recently backed up your Windows 7-based PC or your Windows Vista-based PC as a safeguard. By using the automatic backup functions, you can schedule regular upkeep for maximum convenience.
Many issues can be resolved by simply checking to be sure that all of your plugs are connected properly. After you are sure of that, try restarting (“rebooting”) your system. Turn your computer off, and then back on a few seconds later. If the problem continues, follow the steps below.
Write down the contact information for Microsoft Customer Service and Support, should you need to consult an expert. Take a second to print the below instructions as well, and keep them handy as you walk through the troubleshooting process.