You can make a difference in the Apple Support Community!

When you sign up with your Apple Account, you can provide valuable feedback to other community members by upvoting helpful replies and User Tips.

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

User profile for user: RaskDK
RaskDK Author
User level: Level 1
36 points

External monitor problem iMac 2017 High Sierra.

I try to connect a Samsung external monitor to my new 2017 iMac, but the monitor isn´t being recognized. I used the same monitor with my 2012 Mac mini and it all worked fine (even with two monitors).


I use a new USB – C 3.1 to DVI adaptor, but my iMac isn´t recognizing my Samsung monitor.


I have just updated to Mac OS High Sierra and it still doesn´t work (it didn`t work with Mac OS Sierra either).


And yes, I have opened up system preferences and Displays. Using my Mac mini, the Samsung display showed up in preferences.


Searching the net, it seem to be a problem for many people, but I cannot find a solution.


Any suggestions?


Thank you.


Jesper

iMac, macOS High Sierra (10.13), null

Posted on Sep 26, 2017 6:28 AM

Reply
Question marked as Top-ranking reply
User profile for user: Manicek
Manicek
User level: Level 1
9 points

Posted on Oct 4, 2017 6:15 AM

Also having a problem after updating to High Sierra. I have one display connected with displayport and a second display connected with HDMI. I cannot get them to work at the same time. The mouse cursor is displayed on both, but one of the displays is always completely black. Which one works seems to be random and changes when I unplug one of them and then plug it back

View in context
235 replies

External monitor problem iMac 2017 High Sierra.

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.
Learn more Sign up