Currently Being ModeratedDec 4, 2012 2:23 PM (in response to NDH1958)
May be this will help. Monitor the More Like this box for additional threads. It seems a lot of others are having problems:
Currently Being ModeratedDec 5, 2012 7:00 AM (in response to Eric Root)
I followed your link -- it suggested I reboot in safe mode with the TV connected (I'm connecting through mini-port to HDMI). No luck.
I also followed several "more like this" links -- found others have similar problems, but no help.
It would seem something happened when I upgraded to Mountain Lion. Really wish I hadn't done that. If there were a way to return to the previous OS and test the connection. Then if I could return to Mountain Lion and test there, that would be a way to confirm if it is Mountain Lion.
Currently Being ModeratedDec 5, 2012 7:57 AM (in response to NDH1958)
I called Apple support. The good thing is they took my call and didn't charge me an applecare Pay-per-incident phone support.
Their suggestion is to reinstall Mountain Lion, original version.
I do that by:
Restart the mac with option key pressed down to get to "Start up manager"
In "Start up Manager" I am to Choose recovery HD
Under Recovery HD I am to choose the option to reinstall OS to install 10.8
He said it will take a good hour to reinstall, so I'll try tonight.
His guess is that when I originally downloaded Mountain Lion that a kernal was missing -- one that drives the mini port. If that's the case, Reinstalling the OS will fix the problem.
If that doesn't work, he is sending me to a mac store where they can boot my mac with an external drive -- and then they can check the hardware - the mini-port - to see if the problem is my mini-port or Mountain Lion.
Currently Being ModeratedDec 5, 2012 1:46 PM (in response to NDH1958)
Ok - though no one is following this -- just in case ....
so, I did the reinstall of Mountain Lion -- no luck. I still can't get any connection/recognition between my mac and an external display -- video projector this time.
So, I'll be making an appointment at the Apple Store -- hope I don't get charged!
Currently Being ModeratedDec 5, 2012 5:53 PM (in response to NDH1958)
Good luck. If the Apple store can get it to work, please try to post how they did it to help others. If you mark the post as this solved my problem, it will standout more.
Currently Being ModeratedDec 7, 2012 11:33 AM (in response to Eric Root)
Well - the good news is the Genius Bar determined my problem - it is hardware, not software.
They booted my computer to an external drive, in that way establishing that there were no software problems. And once booted, it was clear my mini display port doesn't work.
Options are to send it out to get it fixed - but given that I don't use the external display that often -- I guess this is the first thing to go wrong in my 4 year old MacBook.
If I did the whole thing again, I would have gone to the Genuis Bar first. It was easy to set up the appointment and the service was great and they didn't charge me anything.