Go to the HP and Toshiba website, find the Windows 10 drivers for your specific computers, then download and install them.. During the normal upgrade to Win10, the default drivers installed are those by Microsoft and on most of the upgrades I've done, it appears like they replace the graphics driver with Microsoft's version. It's usually not the best one for your machine. Being a screen zoom problem, the latest graphics driver provided by those manufacturers might fix the issue.
Hope this helps.
Since upgrading my HP and Toshiba computers to windows 10 I have spent a lot of time resetting the screen zoom back to 100%,as it seems to want to increase or decrease on its own. I have made sure the setting in the control panel is correct and tried adjusting the sensitivity. I want to leave it at 100% at all times. Can I add a command to the registry that will lock it, or how do I solve this, as it is sometimes quite annoying.