My Dell WM123 wireless mouse's middle button has stopped working. Clicking the scroll wheel in chrome used to open new tab or clicking it on any app pinned to the taskbar used to open another instance of the app. Suddenly it has stopped working. I have restarted the laptop and also tried to uninstall & reinstall the mouse drivers. Nothing is working so far. TIA.
I had the same problem with a Logitech G602 mouse. The issue was with hardware button. I opened the mouse (mine has screws hidden behind plastic pads) and put some WD40 on the button just below the wheel. I let it dry a bit, move and used the button several times and added again some WD40 and repeated the click and shake of the button. I reassembled the mouse and voila! the middle click button is working again.
As a comment suggested, you should try your mouse on another PC known to support middle click in order to make sure that the problem comes from your mouse before opening it.