My laser printer is doing funny things.

[Dag77]

I have Windows 10 and installed the Recommended package from HP for my Color Laser Jet Pro MFP M377dw. 

Not only it kept printing countless pages with a few lines at the top of paper (I had to cancel it and reboot the PC to stop it), but trying to print two pages per sheet has been frustratingly unsuccessful, only printing one page on half of the A4 in a

landscape orientation and not printing both pages as I instructed it.

Just one. I'll share a few screenshots for you to see and perhaps somebody will be able to advise me what I can do. I tried different methods from the application, one prints in colour, other just monochrome (two options to choose from to print:).

I shall add, that I reinstalled this package twice today. Once uninstalled it with its own uninstaller, the second time via Revo uninstaller and removing all remaining traces left behind. The screenshots were taken after the latest installation and rebooting twice (because the countless pages printing continued after the second installation, too).

There must be a bug in that installation or something, I have no idea. I had this happening a few months ago after I reinstalled the whole PC and installed this software back then as well. Pages and pages with few lines at top. 

Besides, what other drivers or software do I need to install, as per the prompt by the installation software when finished? I have no idea. What more options? Where? This wasn't clickable in the image. 

This is what I installed today, twice. 

Below the funny things: it doesn't preview the printing with two pages per sheet, but it will print only one page in portrait orientation, as for a book, on one A4 sheet, i.e. just half of what I needed and set up to print. 

This was totally weird when I tried the page settings... Why does it do it? I need two identical table in A5 size next to each other on an A4 paper. I could print this way before, what happened?