Second External monitor not working after update Sonoma 14.6.1

I had exactly the same problem after the update to 14.6.1. I tried every thunderbolt port. Unplugged monitor power. Tried using thunderbolt via a dock, nothing worked.

Eventually I tried unplugging the USB-C cable from the monitor side and plugging it back in. Voila! Monitor sprung back into life. Maybe this will help you too.

I had the same issue, updated to Sonoma 14.6.1 and monitor stopped working. I just found a solution that worked for me though (after many hours of unplugging, reconnecting etc.) - on my Dell monitor I accessed the menu, then went to input source, and for some reason it was on 'VGA' even though I was plugged in via HDMI/USB-C. I changed the input source back to HDMI an voila, everything is working again. Hope this helps someone else.

Hi! Same here, but following process fixes the issue:

• Disconnect thunderbolt cable from your laptop
• Disconnect M8 monitor from power outlet.
• Reconnect M8 monitor power outlet.
• Reconnect thunderbolt

I hope that helps

I reseted my monitor while plugged in via USB-C and it worked.

Just updated to Sonoma 14.6.1 last night. Left monitor not detected after. As I’m typing this, get the low battery message, but everything is plugged in. Disconnected the USB-C cable and reconnected to back of the docking stations and like magic, everything is working again.

Same. However, unlike those below I've had no luck in fixing this. Various rounds of unplugging and powering down, etc. I work on a single external monitor with the mac closed. Never had a issue until just now when installing this update (14.6.1). I use HDMI cable through a iVanky FusionDock 1+. MacBook Pro M1 2020. No ability to use thunderbolt cable with my monitor.

I've got the same issue. (macbook pro 2019) 14.6.1 was installed during the night and on the morning, I couldn't use both of my external screens.

If I plug only one of them, it works.

I tried to plug them one after another, reboot my computer, changing settings on my macbook & on the screens ( reading that some of you add VGA output enabled, that's unfortunately not my case ).

I run into some tutorial to force detection of new screen but its not working either.

Not sure why an update broke important feature like that.

Can this be fixed in a near future ?

I've encountered a similar issue after upgrading to macOS Sonoma 14.6.1. Before the upgrade, my Dell U2719D display worked perfectly with my 2018 MacBook Pro 13". However, after the update, the MacBook screen starts blinking whenever I connect the display. I've tried various troubleshooting steps, but the problem persists.

Same issue since update.

Mac mini 2018. update to 14.6.1 & now only one Apple Display Monitor possible.

All variables of power off/reboot/unplug/ fingers in the air result in one blank display .

Hoping Apple will suggest a fix .

Test twice - update once.

I am having the same exact problem with 2 Samsung S9 Viewfinities. I am unable to get the second monitor working after it was working previously. All combinations of power and TB plugging and unplugging do not seem to help.

Thank you - same issue with my M8 and this process just worked for me.

Still not working and all sorts of resets, hardware changes, and more have still not worked

did you ever figure out a way to make it work

The same problem was revealed today, Sonoma 14.6.1 (23G93). External monitor stoped working.

But this advice saved me. Thank you!

This is what worked for me.