iOS 12.1.2 Xcode Version 10.0 (10A255) can't load build into iPhone six

Question

Xcode : Version 10.0 (10A255) iPhone6: iOS 12.1.2

My Xcode was running smoothly but after coming back from Christmas holiday I get the following error.

I searched around and try to rename the following file 12.0 (16A366) to 12.1 but it is still not working. I have also tried to reset the networking on iPhone and reboot the Mac and still it is not working.

Answer 1

Xcode 10.0 does not support iOS 12.1. Update to Xcode 10.1 to be able to run your project on an iOS device running 12.1. Refer to the following article for more detailed information:

Xcode and New iOS Versions

Answer 2

You have two choices:

1. update the xCode to lates version
2. download desired version's DeveloperDiskImage file(s)

for last one you can download lates files from https://github.com/filsv/iPhoneOSDeviceSupport.

In your case, I had your problem too and because 12.1 (16B91) version was not available(in the Git link),I download 12.1 (16B91).zip and copy to DeviceSupport dir and the problem was solved.