Nearly all computers need to be reset to factory settings eventually. Depending on how much work you do online and how many programs you need to use, it could take a long time or a relatively short time to get to this point. Computer manufacturers at one time included recovery CDs with every computer. Now some manufacturers, including Hewlett Packard or Compaq, simply include a hidden partition on the hard drive that you can use for recovery.
Back up any files that you may want or need to save.
Disconnect any nonessential devices such as printers, USB drives and any other devices that are not essential to computer operation.
Turn On the Computer
Turn the computer On and wait for the logo screen to disappear. When it does start, continually press the "F10" key at the rate of about one time per second. This brings up a recovery menu.
Select the Type of Recovery
In the recovery menu select either a standard recovery or a destructive recovery. For a standard recovery select "Next," and then click "Yes." For a destructive recovery click on "Advanced," select "Destructive Recovery," and then click "Next."
Note that a destructive recovery reformats the hard drive, completely erasing any hard drives attached to the computer including and USB drives, so if you want to keep the information on these drives intact, you need to disconnect them from the computer.
Give Responses to Screens
Each screen that comes up needs to have a response. Follow the screens giving responses until the system recovery is complete.
Once the destructive system recovery is complete, the computer is back at factory default condition. You need to reinstall any software that was installed after the computer was manufactured.
If you do not do a destructive recovery, your files should still be intact. However, you may need to reinstall any software that was installed.
Be sure to check things such as your internet connection as it may need to be reconfigured. Also make sure to update any antivirus programs so that your computer can stay safe.
Update Microsoft Windows
The final thing that needs to be done is updating Windows. Microsoft is continually posting updates and security patches that will need to be updated.