• MacBook 13″ Laptop connected to an external display, external keyboard, USB headset, USB backup drive, wireless network, wired network and a bluetooth mouse
  • My home office
    Daytime Population: 1 me, 1 cavoodle, 1 cat

Events leading up to problem:

  • No configuration changes or software updates for over a week
  • Everything working fine when I left my computer to make a cup of tea for 5-10 minutes and returned to find the symptoms below


  • I can’t left click on anything. Not with the trackpad, not with the mouse
    • This is very frustrating. You can’t easily launch, close or do much that is useful – even to diagnose problems
  • The keyboard still works, so I can type things and use keyboard shortcuts
    • I started to Google Mac Accessibility options so I could accessibility my way around diagnosing this problem
  • I can right-click things

What now?

I began the problem isolation process, poking around, turning things on and off… trying to get to the minimum configuration that showed the symptom.

Until I noticed I had two bluetooth mice.

Crazy! I thought. This Mac has gone insane. I rebooted it and reset the NVRAM and it came back up with two bluetooth mice.

Now, like Agatha Christie, I will reveal to you that one clue that might have made it obvious to you from the beginning.

Cleaners worked on my home office yesterday. They moved my laptop bag so that it was balancing on another bag. I had repositioned it in a safe location when I went to get tea.

Hey, didn’t I put my old bluetooth mouse in my laptop bag?

I hunted around in the bag and sure enough my old backup bluetooth mouse had switched on when I moved the bag. It had been squished so the mouse button was held down.

Coming clean

This is probably something experienced all the time by road warriors with a wireless mouse, but I needed to write it down for google-fu and my future self.