Hi,
Turn the key to REG mode. Press clear (CL), then type some numbers on the numeric number pad. If you see the numbers on the display, then you probably need to log on:
Press clear (CL) then 1 then CASH# (this is not the normal CASH button - it must be labelled CASH#)
If you don't see numbers when you type on the numeric pad, you can try a program reset (this will not lose any data, just restarts REG mode):
Press clear (CL)
Turn power off at wall
Turn key to PGM mode
Hold down the PAPER FEED button
Turn power on at wall
Let go of PAPER FEED button
If it works, the printer should print "**** 2"
Now turn back to REG mode and try it.
If those two suggestions don't fix it, post another question and I'll try to help further.
Mark, February 2009