Apple - Can't restore or update IPhone - TATSU declined to authorize

Mac

If you're using a Mac, follow these steps:

  1. In the Finder, choose Applications > Utilities.

  2. Open Terminal.

  3. Type this command and press Return:

sudo nano /private/etc/hosts

  1. Enter the password you use to sign in to your computer and press Return. >You won't see text appear in the Terminal window when you type your >password.

  2. Terminal displays the hosts file. If you don't see a window similar to the one below, make sure you're using a nonblank administrator password.

  3. Navigate using the arrow keys and look for an entry containing >“gs.apple.com”.

If you don't see any entry containing gs.apple.com, then the hosts file >isn't related to the issue. Close the Terminal and move on to the next >section of this article, "Address TCP/IP filtering, firewall, or security >software."

  1. Add the # symbol and a space ("# ") to the beginning of the gs.apple.com >entry.

  2. Press Control-O to save the file.

  3. Press Return when asked for the filename.

  4. Press Control-X to exit the editor.

  5. Restart your Mac.

After your computer is finished restarting, try to update or restore your >iOS device again.

https://support.apple.com/en-ca/HT201442

That being said, there is no such entry in my /private/etc/hosts or in my /etc/hosts file, so I will look for other solutions to this error.