Hi there and welcome
First, ensure you have backed up all data as this will remove all data from the computer.
Then power off the Acer.
Hold the ALT key and with it held down, turn on the Acer and keep tapping F10 until you get to the recovery manager.
Follow the onscreen steps and you can then perform the factory restore which will restore it to as new.
If you have any problems, or would like any additional information or assistance, please do not hesitate to let me know.
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