@Artur5 inks are third party, refilled original containers. Never gave any problems before.
Nozzle check leaves no traces of color on paper – it's as blank as it goes in. No changes after 3 or 4 cleanings (at least 2 deep cleanings).
I didn't know I wasn't supposed to do more than one cleaning...
I have Canon Imageprograf Pro-300 which was sitting unused for about 6 months. It worked before. It does not print now.
Everything that is supposed to – moves inside, but the paper comes out blank. Tried "Nozzle Check", "Print head cleaning" (both cleaning and deep cleaning) multiple times...