External monitor problem iMac 2017 High Sierra.

Is this new for the mini? I have a for year old mini with High Sierra running two monitors just fine...

🙂 T H A N K Y O U d3vinda!!

I have been searching online for weeks for a solution to this monitor issue. I am very, very grateful. It was starting to do my head in. Best wishes for a happy new year

Hey,

I have a solution Above

Hopefully that will work.

Good luck 🙂

Best

Youssef

Thank you!!! We spent hours, were about to give up and then we found your solution! It worked. Thank you!

what was your solution?

DisplayLink update did not fix my problem.

Hey, could you send the link to one you get? I have DVI to HDMI and it doesn't work with my Dell monitor :-/

Thanks! That worked!

Hi,

I ran two monitors (and also used my MacBook Air's screen as a third display) through a thunderbolt dock, one using a thunderbolt to DVI adaptor the other a USB to DVI adaptor on Sierra, now with the upgrade only the thunderbolt to DVI monitor works. I have tried changing the monitor, the cables, swapped over to a HDMI to DVI cable which made the HDMI monitor work but stopped the thunderbolt one from working, even changed the dock to a Belkin one (which also used to work in dual screen mode). Found an article about how to roll back to Sierra, but this failed so I'm now using a complete clean install of High Sierra, but stuck with a redundant monitor and it's affecting my productivity.

This problem started for me last spring, when I was still running el capitan. My computer never had an issue connecting to two external display monitors, one through a mini displayport to vga adapter and the other from a usb to vga adapter, until one day the usb/vga-connected monitor stopped being recognized. I took the adapter home to test on my old monitor there, and it worked fine. I brought it back to work and tested it with a couple of colleagues' monitors, and it wouldn't work. I couldn't figure out why the adapter wouldn't connect to work monitors, so I ordered a different adapter. The new adapter didn't work, either, and the problem wasn't fixed when I updated to Sierra.

The info I received from Apple Support may be relevant (although not helpful) to those who have posted here:

"The MacBook Air supports up to one external display:

MacBook Air (13-inch, Mid 2013) - Technical Specifications

"The MacBook Pro models can support multiple external displays:

https://support.apple.com/kb/sp690?locale=en_US

So according to Apple, dual-external monitor displays will only work with MacBook Pros and not MacBook Airs. That's the dead end I've reached, which may or may not be useful info to others.

Same here. I am able to get the external monitor to come back on by unplugging the Apple Mini DisplayPort to VGA adapter then plugging it back in to my external Thunderbolt 3 dock. After that, if the Mac goes to sleep and I try to wake it, there is no response unless I unplug and plug it back in. Occasionally the resolution will become stretched out. Unplugging and plugging back in solves that problem, but this is not ideal. At least I don’t need to restart the Mac each time.

Hey :-) While I don't want to deny you a nice new monitor if you want one, but my three not-so-new ones are now suddenly back up and on. I'm not sure how I fixed it. I tried using Apple TV for a bit, that didn't really work, but what was curious was when I did get the Apple TV to link up to my 2011 iMac, it showed a desktop image I have used for ages, so not sure wherever one of the caches plays a part here..? All 3 working fin now though!

OK... There is no official timeline on this but...

Apple Seeds Third macOS High Sierra 10.13.1 Beta to Developers | MacRumors Forums

Lets hope this answers all our issues...

macOS High Sierra 10.13.1 appears to focus on bug fixes, performance improvements, security enhancements, and other under-the-hood changes, but it also introduces a range of new Unicode 10 emoji...

One thing is for sure the emoji team is not slacking!

Matthew

That's a good point, because I was thinking of having to do the same thing this weekend. I dont think it's a software issue, in the sense that this is something Apple chose to do. There would be little to be gained by alienated a large proportion of your customers, after all. In their defence, I have an HD Ready TV which I use as a 2nd monitor (of 3) in my music studio. That worked initially straight after the upgrade, but I had all sorts of interesting fun and games working out that Accessibility had gone a bit bezerk during the upgrade, and afterwards a large rectangle followed my pointer around the screen! Bizarre! Once that was fixed - that was the moment I lost the TV monitor. It's struggled to connect during the week, which actually led me to assume the screen itself had gone, not that there was a problem connecting. I think this is a 'junction' issue in the sense that my original problems arose from Accessibility, which is a hub for all manner of inputs, not least screen sharing and displays. So I'm going to hang fire for a few days and hope Apple fix this, as I can see this is something adversely affecting a great many of us, and spoiling what in many other ways I've found a wonderful upgrade...