Hi and thanks for your question!

Vertical lines are typically caused by the drum wiper blade not cleaning the toner off causing it to deposit on your page...If the blade is not physically damaged, you may be able to fix it without having to buy another toner cartridge.

Is this a pixma 860?

I noticed you put MC860, if it is the Pixma then you are running ink, if it is the 860, then it runs toner...I believe you have the Pixma MX860 running ink currect?

OK, since you are running ink, then you arent dealing with toner. What color are the lines? and do they tend to fade at any place on the page?

Does the lines show when you copy something also, or just from your computer?

Here are some things to start the cleaning process:

(1) Open the printer and wait for the carriage to slide over
(2) Remove the ink cartridges from the print head.
(3) Use cotton swabs dipped in hot water to thoroughly clean the print head and each ink cartridge.
(4) Repeat this until there is no ink residue coming off on the cotton swab.
(5) Once finished, allow to dry and replace the cartridges
(6) Try to print something now

Aboove are the steps to clean the print heads if cleaning the ADF does not work..