Cannot run iOS apps on iMac

OS: OS X 10.13.4

Xojo: Xojo 2018r1

Steps: Not sure what has happened, but using Xcode Version 9.2 (9C40b) and Version 9.3 (9E145), and cannot run iOS apps that I built on MacBook Pro, same settings…
I have the same setup on a MacBook Pro, and have no problem running, building and deploying apps to my iPhone.

I have a Pro licence

Expected Result:
Ability to run iPhone apps

Actual Result:
Can create app, but cannot run them

The only difference that I can see is that when I look at the iOS debugging simulator device setting on the iMAC, I cannot see any devices listed. It seems that this copy of Xojo cannot find any simulators.

Can anyone point me to the solution to this problem?

Thanks in advance

Have you opened Xcode since updating?

Start Xcode and install additional tools.

d’oh
Thanks for replying. Have reopened, shutdown, rebooted, updated Xcode, reinstalled Xojo
Have installed additional tools in Xcode.
I can still write apps on my MacBook, but miss the big screen. Not working on the iMac

Make sure you sign in to your Apple account in Xcode and download development certificates as well.

[quote=385067:@Philip Cumpston]d’oh
Thanks for replying. Have reopened, shutdown, rebooted, updated Xcode, reinstalled Xojo
Have installed additional tools in Xcode.
I can still write apps on my MacBook, but miss the big screen. Not working on the iMac[/quote]
Hi Philip, open Xcode Preferences on each Mac, and check the Locations tab. What is shown for the Command Line Tools setting?

Thanks Gavin and Greg. Getting late here in Australia. Will try those things first thing in the morning

Gavin - it was the locations tab I was missing. Had the command line tools set to an older version. I changed it to the more recent command line tools, and it is now running in the Simulator.
Thank you - I knew I was overlooking something simple, but couldn’t put my finger on it.