Thanks for your kind reply. I am continuing to get the error with Xcode 26.0 beta 5 having fully updated my system. It's possible that I'm doing something wrong, but the error is so ambiguous it's hard to troubleshoot. In an earlier Xcode beta I saw a message about the icon file having an issue with transparency but it disappeared by itself after an update. If I can, I will try a new, blank, icon, in case the icon is somehow corrupted.