This question already has answers here: After switching mouse buttons is with xinput, each computer restart resets the settings (2 answers) Closed 4 years ago .

I am using 16.04 and have a Polaroid wireless mouse, which has worked perfectly until I rebooted my laptop about fifteen minutes ago. When it started back up, my mouse buttons were the wrong way around (as a leftie, the first thing I do when I install a new system is to change the buttons so that the right side is the primary button).

I've tried going into "Mouse settings", and no matter whether I click "left" or "ight", the mouse stays the same. I've tried creating an "Xmodmap" file in my Home folder and putting in a "pointer 3 2 1" line, and it stays the same.

Can anyone help, please? It's driving me mad!