Brother MFC-L8600CDW - Manual (Page 131)

Troubleshooting
119
B
Unusable Device
Remove the
Device. Turn the
power off and back
on again.
A defective USB device or a
high power consumption USB
device has been connected to
the USB direct interface. Unplug the device from the USB direct
interface. Press and hold down to turn the
machine off, and then turn it on again.
Unusable Device A USB device or USB flash
drive that is encrypted or not
supported is connected to the
USB direct interface. Unplug the device from the USB direct
interface (see the specifications for supported
USB flash drives in Printing from a USB flash
drive or digital camera supporting mass
storage on page 67).
USB
Write-protected The protect switch of the USB
flash drive is on. Turn off the protect switch of the USB flash
drive.
WT Box End Soon The waste toner box is near the
end of its life. Buy a new waste toner box before you get a
Replace WT Box message.
Error Message Cause Action