Our school is moving to G Suite for Education. I want to migrate all of our faculty's old emails to the new suite, but am getting an error message re: admin name and password. I've tried the overall account name and password, and I've tried my email and password, but both fail. Any ideas?
It looks like you have already changed the mail service to Google. The only way you can migrate the existing messages would be to set up a POP client and download all the messages. But you won't be able to do that because the client will try to connect to Google. Have you checked to see if Google can assist you with this?