Thank you for using the Support Forum. The code 303-450 you saw indicates a possible issue with the print cartridge. If you only got the code once and it cleared with a power off power on then the machine may have just needed a reset. If the code returns please try the solution in the link I provided above and if that does not work please consider contacting your support centre for further assistance.
Got a fault code of 303.450.00. This has happened only (1) time. Had to disconnect power to shut it down as it was locked up tigher than a drum. Tried googling the code / the Xerox support page for that printer / using ctrl panel access to see if an explaination is there (it told me what the code was but not what triggered it.
I don't know if it's just me but any time I've tried using the Xerox support page it's not correct. Any of you folks have the same problem?