Lexmark C910 User Reference Manual page 198

Enter PIN:
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What this message means:
The printer is waiting for you to enter your four-digit personal identification number (PIN).
What you can do:
Use the operator panel buttons to enter the PIN you identified in the driver when you sent the
confidential job to the printer.
See also:
Using the Print and Hold function
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.
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