Xcode not supported for iOS 11.3 by Xcode 9.2 needed 9.3

Question

Apparently, with the latest IOS update, my version of Xcode could not build due to the following error.

Could not locate device support files. This iPhone

Answer 1

I recently stumbled upon the same problem, where I basically updated my iPhone X to the newest OS version, and (for reasons I will not go into) had to run the app on Xcode 9.2.

This thread was helpful, but there's one small caveat that even though I downloaded the newest support files from the provided Github project, and put them in the appropriate folder, I was still getting this error:

Say for example you’ve downloaded 11.4 (15F79) but after restarting and running again you get an error mentioning something like 11.4.1 (15G77).

The solution, as I wrote here, was to just rename the folder (so, rename 11.4 (15F79) to 11.4.1 (15G77)), restart Xcode and voila, it works!

Hope this helps someone