After upgrading to macOS Monterey, Sidecar disappeared from my iMac

When I use Displays to connect, frequently the cursor will not appear on the screen extension of my iPadPro. Alternatively, everything will work for a brief period but then the cursor will not work on my iPadPro functioning as a second screen. Very frustrating because everything worked so well with Sidecar.

I'm having exactly the same issues as @GhostImage. Either Sidecar connects with no mouse cursor present (and then goes through a few connect/disconnect cycles before maybe finally working) or Sidecar connects and eventually (but always), the mouse cursor stops functioning on the Sidecar screen (iPad Pro 12.9 3rd gen latest iPad OS and MacBook Air M1, latest Monterey). I wonder if this because Universal Control is kinda in Monterey code base, but not released, so Sidecar functionality now has some regression?

Same experience here. Moreover, sidecar now mirrors the whole screen, not just the selected window. And the mouse stop working after a short time. Just unusable at the moment. I am happy that I've only upgraded my MacBook, while still keeping Big Sur on my main iMac.

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If you must use a VPN consider NordVPN. One of the most respected contributors to these forums and a respected developer has reported favorable about NordVPN.  So it may be more secure than most of the other public VPNs.

I don't have Cisco AnyConnect VPN installed and still having this problem. I think this was a bad change to the system. Frustrating as I use it all the time and have to spend time fighting it, rebooting everything.

I can connect to my iPad Pro since upgrading to Monterey and the latest iOS (12.0.1, 15.1) but the ability to change the resolution for the iPad when used as an extension screen has gone. So, although it's a 12.9 inch screen, my iMac trying to use it as a 5K display. Rendering it essentially useless without a magnifying glass!!

By comparison, I can connect to our Samsung TV as a separate monitor via Airplay/ Sidecar, where there are options on the resolution of the TV.

I have struggled for months with this issue and am so frustrated that the latest OS update has not dealt with this. I need to use my iPad as a second monitor. I keep my Mac and iPad up-to-date. Is this feature so little used that Apple just does not care? It also has nothing to do with a Cisco app because I do not use such an app. Come on Apple, fix this issue.

I don't have any VPN so Add Display works. But what's bugging me is the quality of the display. With sidecard, the display was crisp and fullscreen, now it's shrunk and pixelated. There are black spaces at the top and bottom. I miss the old sidecar. Is there a fix to this? I tried tinkering Display to no avail.

Despite the fact that the Cisco app is said to be the problem, it is not. Many of is don’t use the app and still continue to have the Sidecar malfunction.

Here is my work around: noting that things function as they should for about a week after a system update, I decided to shut down my iPad Pro after using it as a second display. While there continue to be connection problems, the iPad as a display freezes less often and I can use it as a second display for one to two hours. Regularly shutting down my iPad is not my usual practice. It does get me a solid connection for an hour or two though.

I saw this on other answers but I have no "Add Display" in Monterey 12.2.1. Looks totally different than other screen shots I've seen. WTF? My MacBook Pro and iPad are not finding each other even though I've gone over the steps a bunch of times.

Thanks for posting... perfect solution. Odd they don’t at least link to "sidecar" in a search ability so you can find it.

Thanks... That said, is anyone using NordVPN and getting sidecar to work? I am not having any luck, but only just begun trying.

I did try disconnecting the VPN, but not uninstalling it yet.

I have the new 16" MacBook Pro and there is no option under DISPLAYs to ADD DISPLAY? Any ideas?

Thanks!

Thanks for this, very simple to connect now.

Is there a way to fix this? Because I need Cisco AnyConnect installed and active to connect to work, but I'm missing my iPad as screen.