The printer is not reading the old or the new black toner cartridge. Is there a way to troubleshoot it?

Was it a genuine toner cartridge? I bought some aftermarket ink cartridges for my canon. The colour one was OK but the black... The printer kept saying black empty. I put my nearly empty genuine one back and the fault disappeared. Put the copy one in and same result. I bought a genuine black and no problem.

try testing with the old cartridge if possible. If not i still would replace the cartridge. any time a problem arises after a cartridge replacement it is normally the cartridge

The new toner cartridge snap's into the top of the Hopper > just look on the box on how to install it. Once you have pulled the tab till you can read "STOP" push the slid back in and release the toner cartridge and you are done...... Put the empty cartridge into the "G" file

I just changed my black toner this past week, and finally figured out why the cartridges get stuck like this.

First, you must eject the toner cartridge on the front-panel menu:
Menu->Replace Toner->Eject Toner->Black(K)

It will say "Rotating to Black Toner(K)" and then say "Black Toner(K) Ready to Eject"

Now, open the front panel and you'll see the black toner cartridge in front. You can also open the top panel if you want more light on your work area.

Lift the lock handle on the old toner cartridge to the "unlock" position, and here's the part that the Dell instructions don't have:

There are two channels for the toner cartridges -- one on each side. Run your finger down the channel on the right, and you'll feel a small, spring-loaded catch. This catch often gets sticky and won't release the cartridge without some help. Don't force it, but gently move it towards the back of the printer and it should release.

Now the old cartrdige should slide right out, and you can finish per the instructions that came with the new cartridge.

Remove the "new" cartridge, and re-insert the "old" cartridge, to see if _only_ the "new" cartridge causes the error.

Otherwise, take the printer to a qualified technician.

Hi,

To run a quick check on your black toner, insert your old black toner back to the printer.

press on the menu button -> system -> report-> supplier info-> print. and same for your new toner, if it show u both the old n new black toner are under the same serial number. the new toner might be faulty. Invalid toner detected.

get the new toner with the box packing back to the shop for replacement.

Most all new color laser printers employ an RFID reader adjacent to each of the 4 tomer cartridges. There is a unique RFID chip inside (under a small blue slide cover) each toner cartridge. Whan a new toner cartridge is installed, the printer "knows" such and begins a "countdown" of the number of prints that are made which utilize the toner in each of the 4 cartridges. Once a toner cartridge has "processed" the predetermined number of copies you will get a warning that the cartridge is almost empty and must be replaced. After an additional predetermined number of copies are processed, the integral computer within the printer will shut down the printer until the cartridge is "replaced". If you simply "refill" the same or original cartridge and re-install it into the printer, the same RFID chip is in the cartridge and the computer will not reset the print "counter", allowing you to start printing. You have to obtain another couple of new or "re-filled" cartridges (of the same color or black) from an outside source. The printers' internal computer does not keep a complete running list of all of the RFID chips that have been installed and used in the printer (maybe 2 or 3) and then then it is "1st in / 1st out" of the limited RFID memory of the printer. I have been unable to obtain a "Service Manual" for the OKI C3400n printer to determine how to do a "hard reset" of the internal computer. I know there is a way which would allow the "refilling" of the toner cartridges without having to buy an additional 2 of each color.

If you have removed and reinstalled the magenta cartridge several times, it is very likely the cartridge is defective out of the box. If you have another magenta cartridge, put that one in and see if the problem resolves. I'm betting it will. If that second cartridge does work, then return the defective cartridge to where you purchased it - they should replace it without a hassle.

There are many problems like that and its not recommended to change toner from one printer to another.
but you should try: put the old toner (emty) in again, then turn off the printer, change toner and turn on printer again.
if thats not helping, then maybe you have a old FW so you can try to update the firmware.