I opened up messages the other day and was using it normally when it seemed to freeze up. I restarted the app and came to realize the left click wasn't working. Right click still works, as well as typing. I can even respond back to someone just fine, but no left click. This is also happening on Notes, Preview, and iCal so far. Everything is fine on apps like Chrome, iTunes, and iMovie. It's been 4 days since this happened. I've restarted the computer multiple times and scoured the internet for an answer, but nothing. I'm at a loss! PLEASE HELP ME!