Ricoh MP 3351 shows messege SC798 , problems with finisher

Check for:
-broken plastic gear on right side of copier
-paper or foreign object in paper path
-paper or foreign object near fuser

Out of focus - Ricoh Aficio MP C4500 Copier with Print, Scan, Fax, Finisher

SC990 means that the hard drive has failed..... It needs to be replaced with a new one or a hard drive from another copier of the same model. Or you can disconnect the finisher.

disconnect the finisher reset it and then it will be a monster roll

unplug the hard drive and switch on machine, if the problem goes away, then plug the hard drive back in and format it with service code 5-832-001, normally works

Left lower front open door small near the floor, pull out used toner cart.

You just need to go to printing preferences and set the tab duplex. (Opens a tab and you chose which one you want.)
If you want to put duplex by default, go to:
Start - printers - click on the right on your mouse - properties - Printer preferences - and Change the duplex. In the end just click on "apply".

sc 302 - charge roller current leak. strip the drum unit (dmu) and clean the unit

Hello sir; Open the finisher door on the mid of right hand side ther have a cross bar fasten by one screw, loose the screw pull out the cross bar, it will detach from the machine.

possible toner pump