I'm left handed and thus I've switched the functions of the left and right mouse buttons so that the right button is the primary. However, I find that when I'm not using the mouse and thus need to use the trackpad and its buttons, I don't want them to be flipped. I want the primary to remain on the left. Is there a way to have a discordance between an external mouse and the built-in track pad?
In both Windows 7 and Windows 10, the Button tab of the Mouse Properties control panel (Run > main.cpl) shows me a Devices pop-up under Button configuration. That lets me specify whether I'm making settings for either "Synaptics TouchPad V7.5 on PS/2 Port" or "Other Pointing Devices". In particular I can make the Synaptics settings right-handed and the other settings left-handed, or vice versa. I hope that works for you, too. If not, please provide specifics about how your system differs from mine.