You are attempting to migrate email from Google Apps to but the migration job is failing with an authentication error. You have already confirmed it is not an issue with an incorrect username or password.
Your Google Apps account is likely blocking access from “less secure apps”. You can turn this feature off:
- Open the “Less Secure Apps” section of your Google apps account and login as the user you are migrating
- Make sure that the “Turn on” option is checked for “Access for less secure apps”.
- Restart the migration batch in O365