General error messages

Most error messages you see are caused by conflicts with other software. If you see a lot of errors, it might be worth cleaning out your machine. Run a virus scan and a scandisk, and then use a SpyWare scanner to check your system, and clear out any nasty programs that might be causing problems.

You can also try typing the error message into Google and searching for it- this will often uncover useful information.

This program has performed an illegal operation and will be terminated

This is a general Windows error letting you know that something really bad has happened. Of course, it isn't really a very informative message. Again, it's often caused by conflicting software, so try disabling other applications and see if you can find the cause.