I have a 15in Macbook Pro (Late 2013 model) which, until recently, had no problem detecting a VGA projector connected via an adaptor connected to either of the Thunderbolt ports. Today I tried it and it simply could not detect the projector display. The only difference I can think of is that I've upgraded to macOS Sierra since last I remember using this system.

I've tried some other combinations to see if I could figure out what the root cause is, but all of the following options work as expected:

  • connect an HDMI display to the HDMI port
  • connect an HDMI display to a Thunderbolt port via an adaptor
  • boot into Windows 10 (using Bootcamp) and connect the same VGA projector to a Thunderbolt port via the same adaptor

All this suggests it's not a problem with the adaptor, with macOS Sierra using external displays, or with the Thunderbolt ports - just with Sierra driving a VGA display.

Does anyone have any idea what the problem is and how I can fix it?

Edit: I've tried resetting the NVRAM/PRAM settings and I've clicked "Detect Displays" a few times in Display Prefs - no success.

2 Answers 2


Resetting MBP with display plugged in will detect it, they had the same issue with El Capitan as well. Hopefully Apple will fix this bug.

  • This does not really answer the question. If you have a different question, you can ask it by clicking Ask Question. You can also add a bounty to draw more attention to this question once you have enough reputation. - From Review
    – StrawHara
    Oct 11, 2016 at 15:14
  • Thanks for the suggestion - that was something I hadn't tried. Sadly it didn't work in my case. Oct 12, 2016 at 7:37
  • @MrMojoRisin How is "reset the MBP with the display plugged in and it will detect it" not an answer to the question of how to get the MBP to detect the display? Oct 12, 2016 at 7:58

Another person in a different forum discovered that 3rd party mini display port to VGA adapters don't work after upgrading to Sierra. I have tested and verified that this is true as well. At present time it's rather frustrating that Apple is being pesky again with forcing people to buy their expensive adapters. If you are in a rush to use it, buying one from the Apple store seems to be the way to go.

  • Welcome to Ask Different! Please refrain from adding comments in the Answer section, this is for answers to the questions. Once you have sufficient reputation you’ll be able to add comments and ask follow-up questions. To gain reputation, answer questions that are clear and concise. Flagging for removal as not an answer. - From Review
    – fsb
    Oct 11, 2016 at 17:34

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