For reasons not worth going into, I cannot get my previously reliable 6015 to work with any cartridges other than an aftermarket set I ordered some time back. I am trying to find the same aftermarket cartridge, but cannot. They are distinguishable fro other cartridges primarily by the following characteristic: Each of the 4 cartridges has a plain blue label with only the words "6010-NL Laser Toner Cartridge" imprinted; no logos; nothing. The four colors are distinguishable ONLY by a circle about 1/2 inch in diameter at the bottom of the blue label.
Can anyone help?