El Capitan does not detect my external display

After upgrading to El Capitan on my MacBookPro (2015), my external display (27" Dell) is not being detected anymore.

I tried the Thunderbolt and HDMI ports, but makes no difference.

Also tried to re-detect the display (Settings -> Displays -> hold 'Option' -> 'Detect Displays') - but that does not result in a detected monitor.

Also tried to remove the power from the monitor, wait 1 minute and put the power plug back in. Also nothing.

Tried a fresh reboot of the Mac, again nothing.

Any ideas for me to try?

Thank you.

MacBook Pro with Retina display, OS X El Capitan (10.11), null

Posted on Oct 2, 2015 3:19 AM

47 replies

blouve

Level 1

4 points

Jul 6, 2016 2:03 AM in response to appenz

Apple recommended this answer, but it does not work for me. Apple -- are there other fixes that are recommended?

May 26, 2017 4:32 AM in response to castor3

Thanks for this. I got the app and adjusted the settings on my external monitor and so far it seems to work!

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El Capitan does not detect my external display

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