Monochrome EcoTank printers like the are highly regarded for their efficiency, but they feature an internal safety mechanism that locks the machine. When the printer calculates that its internal absorption pads are saturated with flush ink, it locks down completely and refuses to print.
If the pad appears heavily saturated, clean or replace it first. epson m100 resetter nosware free
Disconnect all other external printers or scanners to avoid diagnostic cross-communication. Monochrome EcoTank printers like the are highly regarded