How long was the cash register unplugged for before you bought it? It sounds like it was unplugged long enough (> 60 days) for the internal battery to go dead and the programming has been lost. If this is the case you'll need to MAC (Memory All Clear) the register and reprogram it. The procedure is on pg. 72 of the manual. Post again if you don't have the manual and I can give you the procedure. You'll need a Service key (with a 'C' stamped on it). If you don't have a Service key, you'll have to take it to a dealer to have it done.
Good luck ...
Steve
December 2009
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