Currently Being ModeratedOct 15, 2011 4:51 AM (in response to chandralux)
I am having the same issue with a minor exception. I am on a early 2011 MacBookPro 15" and everything worked fine until I installed Lion.
My HDMI TV is 1920 x 1200 and as such is greater than my 1680 x 1050 MBP
I have not yet tried booting with the HDMI adaptor installed - But nothing else seems to work. OSX detects the TV and even sets the resolution correctyl - but sits there saying 'No Signal'
Had no issue with this on SL using the same everything.
Currently Being ModeratedApr 22, 2012 8:45 AM (in response to Martin Schmitz-Bethge)
I now have the same issue and none of the suggestions above worked in any way. With the same miniport-VGA adaptor, once connected to the projector, the computer obviously recognizes the external projector because it switches to a different resolution - also with the "detect displays" I do get the projector. But the projector continues to say there is no signal. The problem is compounded because, once connected, the computer gets all heated up and becomes so slow that it is almost impossible to adjust any settings or even get to the systems preferences (e.g. to change the resolution of the projector, as suggested above).
Currently Being ModeratedJun 17, 2012 10:37 PM (in response to Martin Schmitz-Bethge)
I am having the same experience as M Goebel, down to the sluggishness of response by the computer. Does *anyone* know what causes this, and what to do about it? I'm a history teacher, and I'm desperate to turn my notes into presentations -- but I can't get the projector to "read" the computer.
Contrarily, is there a projector make/model that doesn't have these issues with MacBooks? I'm frustrated enough to consider buying my own projector, if it'll work with my computer.
While I'm working on a 2-month-old MacBook using OS X.7.4, I had the self-same problem with my previous MacBook, which was a year old & using OS X.6.___.... but did NOT have the problem with my 3-year-old MacBook that was probably using OS X.5 (or an early version of OS X.6).
Currently Being ModeratedJul 30, 2012 12:51 PM (in response to _ratfink)
Last week I had no problem projecting a webcast from my Macbook Pro 10.6.8 via a school projector. This week, after downloading Mountain Lion, it didn't work-- no signal. I've learned what to check for from these threads, but does anyone know if OS 10.8 would make this connection more complicated? I'm using mini display port to VGA.
Currently Being ModeratedAug 4, 2012 1:36 PM (in response to Martin Schmitz-Bethge)
The same problem with my newest mid-2012 MacBook Pro 13 inch, 2.9 GHz Intel Core i7 running Lion 10.7.4.
It has suddently stopped recognizing projectors after 2 weeks since I've bought it. After a day of troubleshooting, I have verified that the VGA video cable and Apple's MiniDisplay Port to VGA adapter were working. And then suddenly everything seemed to be back to normal - and I could connect it again to a projector. But the following day connected MacBook Pro to projector and all I could get was again the black screen with flickering thin vertical whitish lines. I always use extended desktop with the projector.
More troubleshooting... At the end WHAT SOLVED my problem:
(1) Started my MacBook Pro into safe boot:
(2) You may want to try doing this with projector connected or disconnected. Got extended desktop through the projector.
(3) Disconnected MBP from the projector. Restarted MBP as usual (NOT safe boot). So far, after a week of use (and no restarts) MBP was connecting properly to 4 projectors.
Currently Being ModeratedAug 25, 2012 6:23 AM (in response to Wunderkind)
After troubleshooting the above issue, I can confirm that for solution to work consistently one needs FIRST to connect MacBook Pro to a projector and only THEN reboot it into a safe boot.
Currently Being ModeratedSep 13, 2012 3:39 AM (in response to Wunderkind)
thank you so much! u solve my problem perfectly! \(^_^)/
Currently Being ModeratedSep 13, 2012 4:59 AM (in response to Wunderkind)
Thanks a lot ! you have also solved my problem. Take care
Currently Being ModeratedJan 22, 2013 5:41 PM (in response to Martin Schmitz-Bethge)
Deleting the window pref files solved the problem, but only after two restarts. Go figure.