Factory reset

A factory reset, also known as master reset, is a software restore of an electronic device to its original system state by erasing all of the information stored on the device in an attempt to restore the device’s software to its original manufacturer settings. Doing so will effectively erase all of the data, settings, and applications that were previously on the device. This is often done to fix a software issue that a device is facing, but it could also be done to restore the device to its original settings. Such electronic devices include handheld computers such as PDAs and mobile phones. Since a factory reset entails deleting all information stored in the device, it is essentially the same concept as reformatting a hard drive. Pre-Installed applications and data on the card's storage card (such as a MicroSD card) will not be erased. A factory reset should be performed with caution, as it effectively destroys all data stored in the unit. Factory resets can often fix many chronic performance issues such as freezing and will not remove the device's operating system.

Common reasons to perform a factory reset include:

Note: a factory reset may only hide data from the operating system so it appears it no longer exists. This is not the same effect as data deletion, and may not therefore be wholly suitable in situations where the device changes ownership.

Factory resets can be achieved in a variety of ways depending on the electronic device. For some devices, this could be done by going into the device's service menu. Other devices may require a complete re-installation of the software. The following section lists a few common electronic devices and how they can be factory reset.

Computer factory resets will restore the computer to the computer's original operating system and delete all of the user data stored on the computer.

On Windows 7:

Note: Take in consideration that Windows 7 is more advanced to factory reset compared to Windows 8 or Windows 10. If you have no experience or are not capable of factory resetting your PC to fresh install Windows 7, ask for assist from a professional for technical support.

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Wikipedia