Getting this error command /usr/bin/codesign failed with exit code 1 with xcode 9.1?

Question

I am getting this error

/Users/macbook/Library/Developer/Xcode/DerivedData/xxxxx-egjyfcyhdfcgftavbtoudbcgthja/Build/Products/Debug-iphoneos/xxxx.app: unknow         


        

Answer 1

I encountered this problem a few times over the past month and it was always right after I had imported some .png files into Xcode. I was able to recreate the error repeatedly if I imported a .png file that was exported from Illustrator using the "Save for Web" which did not including the resolution meta data that is read by Xcode. (screenshot attached)

But, if I exported the file using the "Export As" setting in Illustrator, set the resolution to 144px, and then imported it into Xcode, the error would disappear. (screenshot attached)

Just make sure to delete the images without the resolution listed and you will hopefully be good to go!