Brother DCP-8250DN Basic User's Manual page 84

Error Message
Unusable Device
Remove the
Device. Turn the
power off and
back on again.
Unusable Device
Wrong Paper Size
76
Cause
A defective USB device or a
high power consumption USB
device has been connected to
the USB direct interface.
A USB device or USB Flash
memory drive that is not
supported/is encrypted has
been connected to the USB
direct interface.
The machine can not find
paper of the same size in any
other tray after the tray
currently in use has ran out of
paper during a copy operation.
Action
Unplug the device from the USB direct
interface. Turn the machine off and then on
again.
Unplug the device from the USB direct
interface.
See the specifications for supported USB Flash
memory drives in Printing data from a USB
Flash memory drive or digital camera
supporting mass storage uu page 34.
Load the paper in the paper tray shown on the
LCD.