My C1765nf wont accept any new Cyan cartridges.

Try updating the printer firmware. The problem may be that the circuits that detect low or no ink do not get reset when replacing the ink cartridge. What may be happening is that when the ink cartridge is replaced, the printer checks but may write into the cartridge that it is empty.

I have seen this problem on other printers and the new cartridges could not be used in other printers because the smart chip in the cartridge has been over written that it is empty. If this is the case with your printer then you should try to get credit for the unusable ink cartridge from the manufacturer. It helps if you still have receipts.