I bought compatible cartridge for my Brother

In January 2011 Brother update its drivers for your printer due to a compatibility problem. You haven't advised what operating system you're using but you apparently need to update your drivers.

If you are running Windows 7, you will have to update the drivers either from Microsoft Update or Brother. Click on this link for Brother.

If you are running Windows XP, CLICK HERE

did you replace the tonerproperly or not plz sir check for toner over flow

You have the wrong drivers or corrupt drivers on your system.Disconnect your printer and restart.uninstall your printer and download new drivers and reinstall.all should be fine

I found this solution on the web-- Hope it helps.

The HL-2070N gets stuck in a toner end-of-life error condition. Perform the following to clear :
With paper loaded, new toner in,

Open front door
Turn off printer
While holding down the GO button, turn printer back on
When all four LEDs light up release GO button. All LEDs will turn off
Press the GO button 2 times. The 3 LEDs (toner, drum, paper) will light up solid
Press the GO button 5 times
Paper light will be blinking
At this point the toner end-of-life condition has been reset. Close front door.
BTW, I got this from Brother Support. Also, just a reminder, timing is important here so don't pause between button presses.

http://welcome.solutions.brother.com
Try this
[LED Indication]

The Paper LED is flashing.

Meaning of LED Indication
Front cover is open:
Close the front cover of the printer.

Back cover is open:
Close the back cover of the printer.

Paper jam:
Clear the paper jam. To see paper jams and how to clear them, click here. If the printer does not start printing, press the Go button.

No paper fed manual feed slot:
Put the paper back in the manual feed slot.

Memory full:
The printer memory is full and the printer cannot print full pages of a document.

Print overrun:
A print overrun occurred and the printer cannot print full pages of a document.

Clean drum unit:
The corona wire needs to be cleaned.

Oleg Andrukh IT Specialist
PhillyCopiers.com 215 364 3774

turn off printer, remove cartridge and drum and clean internally.
reinstall drum and cartridge and do a test print, hopefully all will be better.

The HL-2070N gets jammed in a toner end-of-life error condition. Perform the following to clear (I have 120 in the field so I know it works!):

With paper loaded, new toner in,

1. Open front door
2. Turn off printer
3. While holding down the GO button, turn printer back on
4. When all four LEDs light up release GO button. All LEDs will turn off
5. Press the GO button 2 times. The 3 LEDs (toner, drum, paper) will light up solid
6. Press the GO button 5 times
7. Paper light will be blinking
8. At this point the toner end-of-life condition has been reset. Close front door.

BTW, I got this from Brother Support. Also, just a reminder, timing is important here so don't pause between button presses.

check that the paper guides on paper cassette are hard up against paper edges

Masking Tape Gives TN-350 Toner a Second Life, August 25, 2008 By C. MACPHAIL "cmacphail3"
After the "Toner Life End" message appears, it refuses to printeven one more copy. Offensive...until you show it who's in charge.

Remove the cartridge and find 2 clear plastic port holes, one oneach side. The printer shines a light through these to decide when toshut you off. But it's too sudden and too early.

Cover one or both windows with a small piece of masking tape. I get about 3400 copies per cartridge instead of 2400.

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