Please Open Door.

hi

find link for all printer solution link

https://www.justanswer.com/printers/62qtp-printer-won-t-respond-keeps-saying-door-open.html

hi

find link for brother printer error

https://help.brother-usa.com/app/answers/detail/a_id/67765/~/how-do-i-clear-the-message-cover-is-open%3F

It sounds as though the laser shutter has stuck down. Open the front door. in the top left corner of the door aperature there is a slot for the door open sensor which also acts as the shutter cover arm. If will have stuck. Just push something into the hole (you wont get a shock as there is nothing electical behind it) You will feel a click. Now close the door and see if it prints now.
Hopefully all should be well.

Check the following steps for fixing Brother Carriage Jam Error :

Open the print carriage access door. Check for any packing material that may be blocking the internal components. Check for an orange shipping lock that may still be in place on the left side. Pull the shipping lock out, if present, and discard.

Remove and reinstall the cartridges to make sure they are properly installed. Lift the front center of the print carriage access door to open it. Lift the door up until it locks into an open position. Press down on a print cartridge and allow it to spring back up. Lift the cartridge out of the printer. Do the same for the other cartridge. Slide the black cartridge into the slot on the left and the color cartridge into the slot on the right. Press down on each one to lock it into place. Lower the print carriage access door.

Check the print cartridges to make sure the protective tape has been removed from the ink nozzles. Remove the cartridges from the printer. Remove any tape or labels. Replace the cartridges into the printer.

Push in on the tab on the left side of the clean-out door on the back of the printer to open the door. Lift the door out of the printer. Check for any paper jams. Jammed paper can block the printer cartridge carriage from moving. Pull any jammed papaer out.

DRUM UNIT "spent"
It can be reset if the printing quality is good
To reset the drum follow the instructions below:
Press the cover release button and then open the front cover of the printer.

Press and hold down Go button until all 4 LEDs are lit. Once all 4 LEDs are lit, release the Go button.

Close the front cover.
Make sure that the Drum LED is now off.
Caution: Reset the drum counter only when you replaced the drum unit with a new one.

Instead of moving the whole green lever to adjust that grey arrow to the envelope symbol, simply push the gray part that has the arrow on it. This will move the gray piece down to the env. symbol and will not move the green lever so you can close the back door. I used to have severly wrinkled envelopes. Now they print out perfect.

Problem Solved!

I have a Brother MFC-8480 DN all in one printer, copier, fax and scanner.

I discovered that envelopes wrinkle because users, like me, didn't know that Brothers built in a no-wrinkle, pass through exit for envelopes, labels and thick paper.

Envelopes were never to be printed by inserting them in the front and letting them wrap around a HOT roller and get cooked and wrinkled. The way it works:

An envelope is inserted in the front and goes straight out the back of the printer through an exit door, completely avoiding the hot roll-through mechanism.

Take a look. On the back of the machine is a large pass through exit door. Just snap it open. You will see one blue lever on each side of the opening. Snap them both straight down to the . . .ta da. . ."envelope icons".

Put three envelopes in the front and they will print straight out the back, perfect and wrinkle free. After printing your envelopes, snap the blue levers back up and shut the door. Takes about five seconds to open the door and snap down the blue levers down/up.

Happy envelope printing.

-Eric

Sounds like the toner cartridge is faulty. I would change the cartridge.

Unplug the power cord for 10 seconds.

Open cartridge door, while open press "clear"

A couple of suggestions

1) Open door and remove drum and toner. Hold Go button down until all lights are on. Put drum and toner back in and shut door.

Another is.

1. Switch off printer

2. Switch on printer

3. Open front door

4. Remove toner/drum unit

5. With the door still open hold down the go button for 1 second

6. Put the toner/drum unit back in

7. With the door still open hold down the go button for 1 second

8. Close the door and press go to test