Canon DR-5020 Instructions Manual page 72

Cause The scanner was turned ON after the computer.
Remedy Turn the computer and scanner OFF, turn the scanner ON and then
turn the computer ON again.
Cause The scanner is OFF.
Remedy Turn the computer OFF, turn the scanner ON and then turn the
computer ON again.
Cause The scanner's power cord is disconnected from the scanner or
the AC power outlet.
Remedy Turn the computer OFF, and correctly connect the scanner's power
cord. Then, turn the scanner ON and then turn the computer ON
again.
Cause The scanner does not support this SCSI card.
Remedy Replace with a SCSI card compatible with the driver application.
4.1 When The Scanner Is Not Recognized
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