When trying to connect to my iPad to use it as an auxiliary screen, I can see the device in the drop-down list, but after about 30 seconds I get a dialog box saying "Unable to connect to "miPad" [the name of my iPad]. The device timed out.
Both devices are logged in with the same Apple ID, both are on the same wi-fi network, and all operating systems are the latest versions.
MacBook Pro 13", macOS 10.12
This was actually a very helpful suggestion. The solution, although we don't know why, was to create a new user, log out from my account and log into the new user's account. That new user's account could not see the iPad at all, but when I logged out of that user and back into my own account, Sidecar started working!
Whether the creation of the new user was relevant or not, I do not know. It's possible the same result could have been achieved by logging out and back into my account. In any case, problem solved!
Hello,
iMac 27" 5K - iPad Air 3rd gen.
I had the same time out message.
I log out, login in to another user and came back to the original user, the iPad disappear from the menu.
It works with the USB connection.
Side Car connection to iPad times out
