To refill OEM HP Brand cartridges, In some cartridges, we need to replace the chip with new one after refilling cartridges, but for some cartridges, chips or chip resetter are not available in the market. Let’s talk about HP 932/933/951/952 cartridges. These cartridges are not easy to refill as we need a special injector tip to inject the ink inside the cartridge. After refilling these cartridges, customer mostly gets this problem as these cartridges are not recognized by the printer after refilling, this is the main problem to refill these cartridges.Either you can replace the chip with new one or to reset the same chip with the chip resetter to bypass this problem. Use 2 OEM cartridge. You can’t refill one & put it right back in — you have to use a different one, but you can swap them out each time. Apparently the printer knows if the previous cartridge was put back into it, but it can only remember the last one, so if you use cartridge #1 & it goes empty, put cartridge #2 in, then when #2 empties, you put #1 (refilled) back in and it should work, and then refill & use #2 when the refilled #1 goes empty.