I'm trying to import a few accounts from Office 365 but keep getting "Invalid User Details" in the migration wizard.

I have followed the troublshooting guide but everytyhing looks fine.

I have created a test SMTP migration using the same account details and the same user details are accepted just fine.

What else can I do?

Edit: Do I need to change the MX records before doing the migration? I was waiting to make sure the migration went smoothly before making any live changes