I have a Samsung ML-1640 laser printer with the starter toner cartridge (that was in it when I bought it).
I also bought a toner refill kit and performed the refill. Worked great for 20-30 pages, printer then stopped, because the toner cartridge has reached its maximum page count ("Toner Exhausted" - red LED).
If you buy a new toner for the printer, it will have a chip on it, that limits it to xxxx pages printed, before the printer will refuse to use the toner cartridge any longer. So if you refill that toner cartridge, you need to reset the chip (an easy operation from what I can see on youtube).
However - I have the starter cartridge, and that does not have the chip, so I cannot reset it. - but still refuses to use the toner. It would seem there is a different kind of reset mechanism, that needs to be done.
How can I make my printer use the starter cartridge again?
Some guides around the interwebs mention a method where you short two lets on a chip while powering it on. It is however a poor google translation from Russian, so it is barely understandable. http://www.scribd.com/doc/45791992/how-to-reset-page-counter-in-Samsung-ML-1640-1641-1645-2240-2241
I tried it and it does not work.