mountain lion can't click the left mouse

Since you can't click anything, my first suggestion would be to try the steps as per this article: HT1379. Many times, this can fix weird glitches that your mac is experiencing, as well as some Bluetooth issues.

I was having the same problem with my iMac. Couldn't left click with the wireless mouse, i tried all the steps above to no avail. I then tried to use another mouse, this time bluetooth and still had the same problems. I decided to see if my trackpad, which sits in the corner of my desk and never gets used, and then i realize that my cat is lying on top of the trackpad which was causing my problem the whole time.

I hope your fix was as simple as mine.

I was experiencing exactly similar problems and based on mcshade311's advice, decided to check the Magic Trackpad I had laying around. There was some stuff on it and that was causing the whole problem! Took the stuff out and everything works perfectly again. Seems simple, but the MTP can definitely cause these kinds of symptoms.

My iMac does the same thing with mountain lion. It started last week but now does it all the time. Withina couple minutes of turning my computer on the mouse only shows a right click and the keyboard does not work. My iMac is also a 2008. I tried the troubleshooting steps here both SMC and PRAM did not work. I reinstalled mountain lion and I still have this issue. It's at the point I can't even use my computer anymore. In fact I am having to type this on my iPhone. Any help or suggestions would be great! Thanks!

I have been fighting with this problem on and off for a few weeks. Only happens now and then but very frustrating when it does.

For me it turned out that a magic mouse for my Mac Mini was on and trying to talk to my iMac which has a USB mouse with a non working left click.

Turned the magic mouse off and all fine.

Most frustrating bit was the dialogs that I couldn't communicate with without a mouse. Apple needs to enable keyboard use for dialogs!

Add me to the list of frustrated "left clickers." 😠

I don't have a mouse. The track pad will work for a considerable time and then the left and right clicks freeze on open programs. I can't click on any of the icons in the open programs nor can I drag an open window. In otherwords all of the open programs are frozen. If I move the cursor over to the dock the track pad works normally. Rebooting fixes the problem but at some point the problem returns.

vjh

I had exact the same problem, and it appeared (after several reboots and a long time of online research) my other mouse was just lying on my touchpad (thanks to our cleaners 😝)

Problem solved now, finaly can start my work :-)

Thanks!

The left click on my iMac started to work like a right click, so I read all of these emails, but none applied/worked for my computer. Then I changed Mouse Preferences by unchecking Secondary click. So I didn't have right-click ability BUT my left click worked. After a few hours, I rechecked Secondary click, and now both clickers are working.

Just had the exact same problem on my late 2009 imac. No left click, this then turned into no right click in addition. Phoned Apple, guy was really helpful. We tried wired mouse i have instead of the MM, still no clicks. Booted into safe mode, still nothing. Tried a SMC reset a couple of times and bingo it sprang back to life on the second attempt. This is the 3rd time i have had this issue in the 3 years i have owned the machine.

Deactivate bluetooth

It seems that if you have two bluetooth mouses in the same room, it can sometimes interfer and make it impossible to click both on the trackpad and the mouse.

Hope this helps someone.

I did just the opposite. It turned out that my built-in trackpad was malfunctioning. I checked in accessibility preferences under mouse and trackpad the "ignore built-in trackpad when mouse or wireless trackpad is present" and solved the issue.

Now I have to take my Mac for repair to fix it but in the meantime I'm working without problem.

Thanks. I was struggling for 2 days and was on the verge of re-installing my mac, but then I saw your simple comment about another bluetooth mouse interferring and realized that I've another magic mouse that I use for my office laptop which was in my office carry bag and the mouse was on.

Hi, I have a 2012 iMac with Mountain Lion. Left mouse turns to right click (like yours). Tried with both Magic Mouse and another wired mouse. So the mouse is not the problem. Did you figure it out ? Its driving me crazy.

I was caught in a similar situation - even if I plug in a USB Logitech it can only swipe and move, but not click. The cause seems to be, that somewhere in the OS X a click on the mouse button was registered, but not released, so the system thinks you are still pressing the key. The solution is the following (for me):

1) check, that there is no book lying on your mouse button (second mouse, trackpad, etc.).

2) plug off all pointing USB devices AND all Bluetooth ones (switch them off or pull out the battery). This will automatically activate mouse keys - you can move cursor with 2 up, 4 left, 6 right and 8 down, and click with 5, also 0 holds and . releases the click.

3) Now you can go to System Preferences and turn off Bluetooth in the Mac. In my case it was enough - I turned it on again, put the battery in the Bluetooth mouse and it started to work normally.

I think it is a glitch somewhere in this software blocks that substitute for the mice cable via wireless. May be in some cases it is more on a side of a mouse, so it would be sufficient to reboot the mouse by taking off the battery.

The PRAM reset may help, also do a SMC reset per iMac SMC and PRAM reset