I keep getting the message, "Toner error, replace drum unit". I have a MFC Brother 8460N. Jane

SOURCE: MFC 8460N giving Toner Life End message

I just solved my own problem. Try it for yours. I had been using several compatible toners for the MFC-8460N with no problems until today, as I posted earlier. On a hunch, I went to the local office supply store and purchased one original Brothers TN550 toner and put it into the printer and closed the cover. Everything clicked. Toner End Life message gone. I then took that Brother toner out and put the compatible one back in and still everything was fine. Am keeping the original Brother toner as a "kickstarter" if it happens again.

SOURCE: brother 8460n - toner error

Hi, This worked for us:

The message "Toner Error" is usually caused by the drum and/or toner
cartridge not being installed properly or if the machine does not
recognize the toner. To clear this message, follow the steps listed
below:

1. Verify you are using Genuine Brother Cartridges. Brother strongly
recommends that you do not refill the toner cartridges provided with
your machine. We also strongly recommend that you continue to use only
Genuine Brother Brand replacement toner cartridges. Use or attempted use
of potentially incompatible tone cartridges in the Brother machine may cause damage to the machine and/or may result in
unsatisfactory print quality. Our warranty coverage does not apply to
any problem that is caused by the use of unauthorized third party toner
and/or cartridges. To protect your investment and obtain premium
performance from the Brother machine, we strongly recommend the use of
Genuine Brother Supplies.

2. Make sure that you are using the correct drum and toner cartridge(s)
for your machine. The part numbers for your model are as follows:
NOTE: Some cartridges can look EXACTLY the same among different models
and will fit the machine even if they are not designed for use in that
model. Verify the part number before using the cartridge(s).

TN550: Toner cartridge (standard)
TN580: Toner cartridge (high yield)
DR520 = Drum unitt.

3. Make sure that the cartridge is not damaged. Remove the toner
cartridge by following the steps listed below:

a. Press the cover release button and then open the front cover.

b. Remove the old drum unit and toner cartridge assembly. Place it on a
drop cloth or disposable paper to avoid scattering toner.
NOTE: Be careful not to spill the toner. If toner gets on your
clothes or hands, wipe or wash it off immediately with cold water.

c. Hold down the blue lock lever on the right and pull the toner
cartridge out of the drum unit.

d. Look at the toner cartridge and see if any parts or pieces appear to
be broken or missing, if so, the cartridge may be defective and should
be replaced.

4. If the toner cartridge is not damaged, reinstall it into the drum
unit. If it was damaged, use a new toner cartridge and reinstall it into
the drum unit.

5. Reset the drum/toner unit into the machine.

6. Close the front cover.

7. If the message "Toner Error' continues to appear on the display
unplug the machine from the wall outlet.

8. Open the front cover and remove the drum and toner assembly.

9. Look inside where the drum was. On the left side wall, look for a
small, black plastic lever/actuator. A flashlight may help see it.

10. Using the palm of your hand, slide it along the left wall in and
out a few times as this may free up the actuator/lever in case it is
stuck. The actuator/lever is spring loaded and needs to move back and
spring forward to operate correctly.

If the lever does not move, spring back or is missing and your machine
is within warranty, you can locate a Brother Authorized Service Center
(ASC) in your area or contact Brother Customer Service by calling
1-877-Brother (1-877-276-8437) Monday through Friday, excluding
holidays. If the machine is out of warranty, you can locate a Brother
Authorized Service Center using the information listed above.

If the lever moves freely and springs back to its original position
continue to Step 11.

11. Reinstall the drum and toner assembly, close the front cover and
plug the machine in.

SOURCE: document jam brother mfc 8460n

if the message refers to the scanner, open the cover of the feeding unit on top of the printer and clean it with compressed air. Most probably an insect got stuck somewhere

SOURCE: Replaced new drum unit but LCD keeps saying Drum Near End of Life

Front cover must be open

Press The "Clear" key on the top panel

Press 1 to reset the drum count

Close the over

SOURCE: Home | Printers | Brother MFC 846CN error...

Try the Control Center update tool.

For Windows XP
http://welcome.solutions.brother.com/bsc/public/us/ca/en/dlf/dlf/000000/003200/dlf003221.html?reg=us&c=ca&lang=en&prod=mfc8460n_all&type2=2&os=7&flang=8&dlid=dlf003221

For Windows Vista
http://welcome.solutions.brother.com/bsc/public/us/ca/en/dlf/dlf/000000/003500/dlf003530.html?reg=us&c=ca&lang=en&prod=mfc8460n_all&type2=2&os=74&flang=8&dlid=dlf003530