harishfromvalrico Said:
"Left Click is not working on my old mac, which is 8 year old. Purchased a new mac book air 2-3 weeks back. After 2 weeks of use, this also has same problem. Apple store is not able to resolve this issue asking us to return the laptop."
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Troubleshooting Left-Click:
Troubleshooting AOL Mail Sysncing:
A. Try Safe Mode:
While in Safe Mode, try entering the passwords. In Safe Mode, login items do not run, and corrupt system files(i.e. caches) are intentionally reset as a way to fix issues. Start up your Mac in Safe Mode - Apple Support
B. Single-Out this User:
Try an Admin new user, see if you can use left-click while booted in to it. If so, then it is an issue with the current user. If not, then it is an issue with the entire macOS or Mac.
C. Reinstall the macOS:
Nothing would be deleted. It's just that items that have become corrupted or deleted, would be replaced or reinstalled back to where they should be. Go Here: How to reinstall macOS from macOS Recovery - Apple Support. Important: (applies if you can log in) Be certain to create a backup of your Mac prior to all of this. That way, you can have something to restore from the Mac from, should anything go wrong with the reinstall. Once reinstalled, try this once more, seeing if you still get this error.