The Reset Key is required when you want to reset Waste Ink Pad Counters in Your Epson inkjet printer using the free program PrintHelp. Scroll down the list of supported models in the program PrintHelp to be sure Your printer model is supported. Connect the printer to PC, and click Check Waste Counters. If the value of any of the counters will be more than 100% you need to do a reset. To do this, click Reset Waste Counters button. If your printer model is fairly new, you may need to enter a reset code, which can be purchased here and get an instant email after payment in any convenient way. Any questions about resetting waste counters - set on the program website PrintHelp