My ML2850 toner cartridge arrived safely. I have only just got round to trying it out. When I did try it I thought that I was going to have to return it as at first I could not get it to print. When I tried to print something a sheet of paper would start coming out of the printer but it would jam with about one third still in the printer. Nothing was printed on the paper. I eventually traced the problem to the 4 contacts that the supplied cartridge has that my original does not have -- see the attachment where you can see that my cartridge has no contacts and yours has four. One has to be a bit forceful in inserting your cartridge to make sure that good contacts are made. My original cartridge goes in very easily. It would be helpful if advice regarding making sure that the cartridge is firmly inserted were included with the cartridge.

Amazing delivery timing. I ordered at 3 was with me by 9 and thats at Christmas