I purchased a new in the box r280 at a rummage store and after installing the new cartridges they were not detected by the printer. Ordered replacement refurbished cartridges and had the same problem with green light toggling and ink lamp amber. Solution: remove the cartridges first, then filled a syringe with alcohol, I used the 91% from Sam's Club but could have used any that is available to you.. Now comes the tricky part, set up a light to illuminate the cartridge carriage and then use the syringe to inject ink into the top of the black plastic post that puncture the cartridge. It looks like there are 4 opening on the top where the ink would flow into the cavity, I did not press the needle into the opening only used the flow from the syringe to clear any contamination. Then removed the excess ink/alcohol using toilet paper to wick it up and ready to test. Then replaced the cartridges and pressed the ink button and after initial loading by the printer it worked for me. Hope this works for you and anyone...