Cleaning Out Unneeded Files revised 7/31/08
Your computer tends to accumulate unneeded files, just as a consequence of normal operation.  Many of these are temporary files created as "scratch paper" by the programs you use, particularly your web browser.  As these files accumulate, their sheer volume may degrade your computer's performance; in extreme cases they can slow your computer to a crawl or make it run dangerously low on hard disk space.  Use the following procedure to "clean house" every month or so (or more often if you do heavy web browsing or your system has become noticeably slower in responding):
  1. Check the Recycle Bin and recover any files that you don't want to lose permanently.
  2. Uninstall any software you don't use; if an Uninstall option is available for the software on the Start menu, use that; otherwise, use Start, Settings, Control Panel, Add or Remove Programs.
  3. Delete any documents and other files you don't need, particularly larger files such as images, graphics, music and videos; if you think you may want or need a file in the future, first copy it to a CD, external disk or other medium before deleting it from the hard drive.
  4. In Internet Explorer, open the Tools menu and choose Internet Options...; select the General tab; click the Delete Files... button; select the "Delete all offline content" checkbox; click the OK button to delete files, and wait for the hourglass to disappear; if you also want to delete cookies, click the Delete Cookies... button, click the OK button to confirm the deletion, and again wait for the hourglass to disappear; when you're done, click the OK button to close the Internet Options window; close Internet Explorer.
  5. If you use the Firefox browser, open its Tools menu and choose Options; in the Private Data area, click the Clear Now... button; make sure the Cache option is selected and click the Clear Private Data Now button; click the OK button in the Options window to close that window; close Firefox.
  6. If you use the Mozilla browser, open its Edit menu and choose Preferences; in the Category box, click the plus sign next to Advanced, then click on Cache; click the Clear Cache button to delete temporary files, and wait for the hourglass to disappear; if you also want to delete cookies, in the Category box click the plus sign next to Privacy & Security, click on Cookies, click the Cookie Manager button, and then either select the cookie(s) to be deleted and click the Remove Cookie button, or click the Remove All Cookies button and then click the OK button to confirm the deletion; when you're done, click the OK button to close the Preferences window; close Mozilla.
  7. Open My Computer, right-click the icon for the C: drive, and choose Properties; click the Disk Cleanup button and wait for the system to assemble the files to be deleted (if you haven't run Disk Cleanup for some time, this could take several minutes); when the Disk Cleanup window appears, make sure that all of the checkboxes under "Files to delete:" are selected, and click the OK button; click the Yes button to confirm that you want to delete files and wait until the progress indicator disappears (depending on the number and sizes of the files involved, this could take a while); click the OK button to close the "Local Disk (C:) Properties" window; close the My Computer window.