Error 400 for Gmail in apple mail on Macbook
IT WORKED! I have an old Macbook and somehow lost my Gmail in apple mail. Tried everything and finally went to Google Security and 2 Step Authorization then added the APP password. Back to Mail and added an Internet account and the app password it worked! All my mail is back, thank you to whoever suggested that in the community. Hours and hours wasted until I found this.
MacBook Pro 15″