Was everything unplugged, including ethernet and usb? If not, unplug EVERYTHING and wait a while before retrying. Probably won't help, but I had a pc that latched up, only giving beep code. It was latched up, unplugging power didn't help, had to also unplug ethernet before it returned to normal. Turned out the power supply detected a fault (usb temporary short) and locked up to prevent damage. Ethernet cable actually provides power, caused supply to stay locked until unplugged.
Also run down beep codes for your printer, should indicate fault of some sort.
Richard Southworth