Sorry to resurect this thread, but I had the 74:01 error on my new 3100 tonight. It's a communications error. I was using a 10' USB extension cable. I have had similar communication problems using extensions with printers, so that's the first thing I suspected. Sure enough just switching to an ethernet connection (and probably using only the supplied USB cable, but who has the computer that close) cleared it right up. The firmware updated, done. Now about these damn roller and star marks...
