Command /usr/bin/codesign failed with exit code 1

Question

I have the following error:

Command /usr/bin/codesign failed with exit code 1

Here is what I already did for trying to fix this:

Answer 1

For me, I just updated to Xcode 8, and converted my Swift 2.2 code to Swift 3 code, and I got errors in the Unit Testing and UI Testing. I just cleaned and then all the errors disappeared.