Issue
Copy has vertical black streaks.
Cause and solution
Appropriate paper is not being used.
Cause and solution
The feeder roller, and the scanning area are clean.
Cause and solution
The fixing unit is dirty.
Cause and solution
The toner cartridge is not installed properly.
Install the toner cartridge properly.
See the "e-Manual" (HTML manual) in the CD-ROM supplied with the machine.