Today I visited this Lexmark X792 in EC4 central London, which was paper jamming. One of the main reason for this fault is due the build up of paper dust, which if left without clearing will cause a lot of damage to a printer especially if the machine is heavily used. We recommend using a qualified printer engineer to do this, as this process does involve taking the printer completely apart and cleaning the fuser unit. Unfortunately this time the build up of paper and dust had caused irrepairable damage the fuser and it had had to be replaced. Once this had been done the printer was back up and running again. One final piece of advice for high volume users who have critical printering needs, I recommend having a spare fuser unit and transfer belt onsite to avoid unwanted printer down time in your office.