EXFO FTB-2 - Manual (Page 294)

Troubleshooting
284 FTB-2 and FTB-2 Pro
Restoring Your Unit to Normal Operation
C
AUTION

Before starting one of the recovery operations, connect your
unit to a power outlet using the provided AC adapter/charger.

DO NOT TURN OFF your unit while the recovery operation is
underway. Doing so may severely damage your unit. Damaged
units will need to be sent back to EXFO for repair.
I
MPORTANT

Refresh operation: All the data that is stored in the default
personal folders will still be available once the operation is
complete. However, any data stored in other folders will be lost.
You may want to back up this data before refreshing your unit.

Reset and restore operations: To avoid losing the data that is
stored on your unit, you may want to back it up before
resetting or restoring your unit. Otherwise, all your files will be
lost.