MSI AE1920 User Manual page 63

MS-A923
[System Partition Recovery] will format the C drive only. Only the C drive
will be restored to manufacturer default. Other drives will not be affected.
It is highly recommended that users select [System Partition Recovery] to
restore the system.
6. The system recovery will format your HDD partition. Make sure that the
important data have been backed up. Click [YES] to continue; click [NO] to
stop the system recovery.
Click [YES] again to reconfirm; click [NO] to stop the system recovery.
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