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Macbook Pro / Sierra /Model 1502
My Touchpad stopped clicking. I could move the pointer around but couldn't click. Then I plugged in an external mouse. Still couldn't click but the right click worked somehow on the external mouse.
After a lot of struggling I managed to disable the Touchpad by using this command
sudo kextunload /System/Library/Extensions/AppleUSBMultitouch.kext. Then the external mouse started to work normally.
But now the keyboard started to act strange. Some letters don't work, some do work but very slowly. Then I connected an external keyboard and it works fine.
Now I am using external keyboad/mouse and have the Touchpad disabled.
Can someone help me to make the original keyboard/touchpad work again. What is the root cause of this weird behaviour.
p.s. I have tried all kinds of reboots. * Command+Option+P+R * Option+Control+Shift