Reformat a Hard Drive and Reinstall Windows Operating System

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If your Windows operating system becomes so damaged or so compromised by hackers and trojan programs, you may need to restore your system by reformatting your hard drive, which means erasing all programs and data on your machine, and reinstalling Windows.

Restoring your system

Most major computer vendors (Dell, HP, Gateway, etc.) provide system restoration software with their computers. This software will format the hard drive, reinstall Windows, and reinstall any of the programs that came with the computer.

Unfortunately, this software cannot back up any data files or programs that you installed independently on your hard drive that you want to save. Before you run your system restoration disc, make sure that you backup any data (academic papers, resumes, contact information, etc) to an online or external location. 

If you no longer have the system restoration software that came with your computer, contact your computer vendor to see if they can provide you with a new copy. Be ready to tell them the information that matches your computer, such as the model number and the serial number so that you will receive the disk compatible with your computer.

If your computer was not built by a major computer vendor or you cannot obtain system restoration software from your vendor, you will have to format manually your hard drive, reinstall Windows, and then reinstall your programs. Before you start this process, you should try and save any important files you need to an external location so you don't lose them during the formatting process. 


Reinstalling Windows

The method you use to format and reinstall Windows can depend on what version of Windows you have and your computer hardware. You must have Windows installation software in order to reinstall Windows. Once Windows is reinstalled, you will have to reinstall your other programs individually.

If you need a copy of Windows, please see Division of Information Technology Software Licensing for information on licensing Windows Operating Systems.


Additional information

If you need additional information on formatting your hard drive, contact the manufacturer of your PC for assistance. If you need assistance with reinstalling Windows, contact Microsoft.