Regular use of a computer and the Internet causes temporary files to build up. These files take up hard drive space, and can cause conflicts if old and new versions of the same program are in your temporary files. To clean up temporary files on your hard drive, click the "Start" button and then click "My Computer". When that box opens, RIGHT click on your hard drive (Letter C:) and click "Properties". This will prompt you with a box with several tabs. On the "General" tab, click "Disk Cleanup" and then let it work. It will take several minutes usually, but it depends on how much temporary information has piled up on your computer.