Upadted to RC, now my MBP 14 M4 wont connect to widescreen

[chasescott66]

Yesterday, I updated to the macOS Tahoe RC(or so we believe), and my computer will not connect to my 34" LG widescreen monitor. I have tried different cables and nothing works. I have tried different devices(iPad and iPhone) and they work just fine.

I even hooked my MBP up to an old regular monitor, and it worked just fine.

I am at a loss for what the issue could be. Has anyone else experienced a similar issue?

 

[CalMin]

It is a USB-C monitor? You could try System Settings > Privacy & Security and set Allow accessories to connect to Always.

 

[throAU]

Have two wide-screen monitors connected to my m4 max right now. I have noticed the machine will finally wake up if I just plug in a type-c monitor now, no need to open the lid and close it.

 

[chasescott66]

It is a USB-C monitor? You could try System Settings > Privacy & Security and set Allow accessories to connect to Always.

No, it is an HDMI monitor.

I did check this, and it is set to always.

 

[chasescott66]

The workaround I did yesterday was to airplay it to my office TV, then stop, it would then pop up on my monitor(very buggy and slow). After that, I could clost it then it functioned normally.

I am at a loss for what is going on.

 

[Fishrrman]

OP:

A suggestion.
May help, or may not.
Try it anyway.

Download and install "BetterDisplay" (if you don't have it already).
See if that can get you going...

GitHub - waydabber/BetterDisplay: Unlock your displays on your Mac! Flexible HiDPI scaling, XDR/HDR extra brightness, virtual screens, DDC control, extra dimming, PIP/streaming, EDID override and lots more!

Unlock your displays on your Mac! Flexible HiDPI scaling, XDR/HDR extra brightness, virtual screens, DDC control, extra dimming, PIP/streaming, EDID override and lots more! - waydabber/BetterDisplay

github.com

(On the right, look at "releases" and then click "latest". On next page, click the black "download app for macOS" button)

 

[CalMin]

The workaround I did yesterday was to airplay it to my office TV, then stop, it would then pop up on my monitor(very buggy and slow). After that, I could clost it then it functioned normally.

I am at a loss for what is going on.

I always used to consider the RC and the x.1 and x.2 releases to be advance betas. In the last couple of years, I've had better luck and have upgraded pretty much on Day 1 - even my primary work machines.

Sorry you're having this issue, but things like this are useful reminders for everyone to just proceed with OS updates with caution if you rely on your Mac to put food on the table.