Several times now I’ve encountered issues where Xamarin doesn’t let me deploy an app under development to an iOS device. In some cases, I’ve found the answer here, but I’m going to lay out the full solution for all cases.
- Register your unique device ID (UDID) at Apple Developer Device List. You won’t have to start here every time. In fact, if you’ve been developing/deploying to your device for a while and Xamarin suddenly stops deploying to the device, this is not the problem. But if you’ve never used the device for development before, this is where you have to start. You can search for instructions on getting your UDID, but it seems the easiest way is to connect your device and view it in iTunes.
- In Xamarin Studio v5, go to the context menu for your iOS project and select: Options > iOS Bundle Signing. You may have to twiddle with the Signing Identity and the Provisioning Profile. In my case, they were both set to Automatic after a XS update, but to get it to work I had to change the Provisioning Profile to iOS Team Provisioning Profile.