So, as I usually cannot get scanning to work via USB, I can scan via Wi-Fi instead. It's a work-around, not a solution, but at least by doing that I can scan reliably as well as print. Of course you can't use such a work-around if you have a model of MFP that only provides a USB connection. You will need root access to complete many of the steps while installing HPLIP. If you do not have root access...