Many Epson printers use cartridges with built-in computer chips that monitor the ink level in the cartridge. Unfortunately, this presents problems if you prefer to have your cartridges refilled (a service now offered through many office supply chains) or if you want to do it yourself. Once the cartridge goes dry the first time, the "smart" chip will continue to report that it is empty even if you've refilled it. The workaround for this problem is to reset the chip.
Buy an Epson chip resetter. Vendors such as Mr. Inkjet, MicroDirect and InkSupply all sell relatively cheap Epson chip resetters that can be used over and over again. Most resetters work by plugging into the contacts on top of the cartridge and using an electrical charge to "fool" the cartridge into believing it is full.
Align the contacts on the Epson cartridge with the notches or prongs (depending on the manufacturer) on the chip resetter. The two sets of notches must line up precisely.
Press the prongs on the chip resetter and the contact points on the cartridge together for several seconds. You may need to apply significant pressure.
With most chip resetters, an LED indicator will blink green when the chip has been reset. Once this happens, the chip has been reset and you may use the cartridge to print.