For many of the procedures mentioned here, you will need to be an administrator, or have administrator privileges.

Having established in the first part of basic troubleshooting that your computer is powered on, the next thing to check is if it boots up normally. We will be talking about Windows XP here, but earlier versions are similar.

The first thing to establish, when you have a problem booting, or even if it appears to boot normally, is if you have recently changed anything. Have you installed more memory, a new hard drive etc., or new software?

Maybe you downloaded some software, or MP3s, or a movie? You stand a good chance of downloading a virus, along with your music!

If you are having a problem booting your system, it may help to boot up in 'Safe Mode'. Safe Mode is a method of booting the system with only the drivers required to run the basic system.

You will be able to use your keyboard and mouse but will see only a basic vga display, and have no network connections etc. This can help, for example, if you had installed a new piece of software, or a new device which requires a different driver.

It may be that the software is not compatible with Windows XP. This should not happen with newly developed software, but does happen.

Another possibility is that the registry has become corrupted, in which case you can go back to a previous state. This is called 'Last known good configuration'.

To boot up in Safe Mode, or 'last known good' restart your computer, and, when the message 'Please select the operating system to start' appears, press the F8 key, (located on the top row of the keyboard). You may need a couple of goes to get this at the right time.

The screen will now show a list of options, select 'use last known good configuration' and hit Enter. The system will retry the boot. If all is well it should boot up ok.

You should now remove whatever you just installed. (Start - Control Panel - Add or Remove Software). Select the item to be removed and follow the instructions. You may be asked to reboot. It is a good idea to do this anyway.

In part 2 we look at what to do next if this did not work. We will boot the computer in Safe Mode.