My Minolta Bizhub c250 has lines of blue and red going though the images. It also seems to be printing Dark. Is this likely a drum issue or something to do with the fuser or transfer belt?

SOURCE: how do you reset the life of the transfer unit on the Bizhub C250

Yes,

Remove Trasfert belt unit.

On the left handled remove one screw ( spring fixer) and remove right srew (over the belt / bar whit finger fixee).

Remove, on the left spring stoppage and metal handled.

Remove black little srew and take to hand fuse contact.

Change fuse (behind) with new identical fuse and reassembly.

It may be reset trasfert belt counter.

Sorry for my not good english.

Bye.

SOURCE: paper feed and colour problems with Konica Minolta bizhub c250

any stripes are usually caused by imagining unit, first use the tool in front cover to clean laser glasses. inspect IU drums for stripes maybe youll need to change them. is the page coming out ok, but picture is printed crookedly ?

SOURCE: Konica Minolta bizhub C250

i think that your fax is not set up right, or maybe the machine is missing admin and machine e-mail address, that can cause too this problem.

SOURCE: Konica Minolta BizHub C451 printing red lines down documents

your imaging unit is damaged. call minolta guys to have a look it at and change it if neccessary

SOURCE: A blue line , 2mm, appearing at bottom of page.

Hi Info39684,
It sounds like your Cyan imaging unit has gone down.
Have you thought of changing the orientation of your paper from A4 protrait to A4 landscape. If the blue line is at the bottom, changing the orientation should hide the problem. It's not going to fix it, and if you use A3 then you will see the line again. It's just an idea and you could save yourself £250 on a new unit.
Regards
Taminol