How to Uninstall and Reinstall Your Operating System
- 1). Back up all of your files. Reinstalling your operating system completely erases your hard drive, and after you are done, nothing of your old computer will remain. That means you need to reinstall all your files from your backup location, so that backup must be up to date.
- 2). Insert your operating system CD and follow the installation prompt. Select "Yes" when it asks if you want to delete your current operating system. If you are uninstalling a Windows OS, continue to Safe Mode to complete the uninstall. Go to your command prompt and type in "DEL WINDOWS" and press "Enter." Hard drive reformatting begins, erasing everything. If you have a Mac, simply follow the on-screen prompts.
- 3). Follow the directions to reinstall your operating system until the process is complete.
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