Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

External display not supported when MacBook Air is closed?

I've explored this issue quite thoroughly before posting; any help would be heroic!


I have a brand new 11" MacBook Air running 10.8.4. I recently bought a used Acer external display (model AL 1916W A), and I'm connecting via Thunderbolt to VGA. The MacBook has been connected to a power source throughout these issues.


Everything was working normally when I first got the display. I adjusted some resolution settings to optimize the picture on the external display, and suddenly I was unable to use the external display when I closed the Air (clamshell mode).


When I close the lid, the Acer display reads "Input Not Supported." This is the same error message I got a few times when I was initially adjusting resolution - for example, if I went to a refresh rate higher than 75 hz, this message would display. However, in all of those cases, the screen would automatically revert back to a functional setting. Now, I close the lid and get nothing but the error message.


Things I have already tried:

  • Reset external display settings to factory defaults
  • Adjusted the resolution on external display with the Air open to various options, including 800x600 at 60hz
  • Adjusted the resolution on built-in display to all possible options and tried closing the lid
  • Reset PRAM
  • Deleted "com.apple.windowserver.plist" file in Library


No matter what combination of display settings I use when the lid is open, it never works when the lid is closed. I'm assuming the Air is reverting to a high resolution / refresh rate to send to the external display when it closes, but I can't seem to adjust this.


Please help! 🙂

MacBook Air (11-inch Mid 2013), OS X Mountain Lion (10.8.4), 1.7 GHz Intel Core i7 with 8GB RAM

Posted on Aug 12, 2013 9:34 AM

Reply
Question marked as Best reply

Posted on Aug 24, 2013 1:28 PM

Update - I ended up spending about an hour on the phone with a very helpful rep from AppleCare. He was also stumped by this problem. We ended up solving it by using a remote screen-share app that allowed him to see what my video card was sending to the external display, and he directed me over the phone to change the settings (quite funny really - it was literally "move your mouse up a tiny bit, now click, now left, etc).


So, my problem is solved for now, albeit in a very cumbersome way. Still amazed that there's no way to fix this properly.

1 reply
Question marked as Best reply

Aug 24, 2013 1:28 PM in response to MrWhoMEye

Update - I ended up spending about an hour on the phone with a very helpful rep from AppleCare. He was also stumped by this problem. We ended up solving it by using a remote screen-share app that allowed him to see what my video card was sending to the external display, and he directed me over the phone to change the settings (quite funny really - it was literally "move your mouse up a tiny bit, now click, now left, etc).


So, my problem is solved for now, albeit in a very cumbersome way. Still amazed that there's no way to fix this properly.

External display not supported when MacBook Air is closed?

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple ID.