Red dots vertically down the page

[vlha2281]

I am also having a problem with red dots printing vertically down the page. I can run a calibration on the color and it will fix it for a few pages, but it always comes back. These red spots show on colored printing, black and white printing, and grayscale printing. I have changed all the parts (toner, waste cartridges, drum, and rollers) and nothing fixes the problem permanently. 

[Joe Arseneau · Accepted solution]

It is most likely the same magenta imaging unit they are telling you to change in your other thread