I refilled a cartridge for my samsung clx 3175 printer and like couple days after the printer is telling me i have a invalid toner. what do i do to resolve this.

Well, eventually I worked it out: The "contacts" are four square fields to the left on on the backside of the cartridge. And it works instantly. (I read somewhere that it needs to be fully transparent tape. The 'blurry' tape leads electricity and doesn't work.)

The cartridge is original? If not replace the chip on the cartridge or buy original cartridge.

There are some infos missing on the chip of the cartridge so the printer dont get the right code and send this error, you can purchase chips from and refill store!

No solution, but exactly the same problem! Is it not possible to install the old firmware? HELP!

I have the same problem in a CLP-300. I have tested 3 diferent aftermarket chips from different manufacturers and always the same message: "invalid black toner" and the black toner light keeps red

if you fill them your self, like i do, it will say "TONER EMPTY" then it will say STOP.
if you press the right arrow, it will say "CONTINUE" then press ok.
This way you should be able to print using the refilled cartiridges, but every time you open the fuser cover, or the printer gets turned on and off, it will ask you the same quiestion.
if you accidently press STOP, dont worry, just turn it off and turn it on again, and it will ask you it again.

Incase you need toenr powder, refill supermarket supply the powder, if you email them, they will give you a link to the requred toner powder.
it costs about £26 inc shipping uk, to refill the printer.

Hope this helps.

Jake

Service Manual can be found here. Free
http://hotfile.com/dl/28988134/55113fe/CLX-3170-3175.zip.html

Takes CLP 310
To use Toner refill you need a chip that solder to the main board. search Ebay for reset chip for CLX-3175
run around $40.
Service Manual Free
http://hotfile.com/dl/28988134/55113fe/CLX-3170-3175.zip.html

the drum has chips encoded,need cartridges with chips.

Refill not recommended. Replacement is the way to go. You can pickup replacement toner cartridges from you local electonics store or where you purchased from.