Q:

Failed to create IXPlaceholder for app bundle ID in xcode 9

I just installed Xcode.  Version is 9.0
I registered myself (personal team) as a team. 
when i am run code then :
Failed to create IXPlaceholder for app bundle ID com.xyz.abc
Thank you! 

A:

I had the same problem, because I unzip and install Xcode on another laptop and then copy application to my own laptop! 
Try download and install it again and avoid copy/paste. Just unzip it in your laptop.