Lexmark C750 User Reference Manual page 83

Fax <x>
What this message means:
The printer is processing an incoming fax.
What you can do:
Wait for the message to clear.
Flushing Buffer
What this message means:
The printer is flushing corrupted print data and discarding the current print job.
What you can do:
Wait for the message to clear.
Formatting Disk
What this message means:
The printer is formatting the hard disk.
What you can do:
Wait for the message to clear.
W :
Do not turn the printer off while this message is displayed.
ARNING
Formatting Disk
yyy%
What this message means:
The printer is formatting the hard disk. When formatting takes longer than usual, the second
line of the display shows the percent complete.
What you can do:
Wait for the message to clear.
W :
Do not turn the printer off while this message is displayed.
ARNING
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