If your email account is provided by Google Mail you may receive an error when syncing your emails for the first time.
If the Google account is attached to an Android Device, you will have a notification here informing you of the unknown login.
Email sent to Back-up Account
If you have a back-up email account set up, the following Email will be sent to you:
Clicking 'Review Your Devices Now' will give you the option to enable the account.
You will see something similar to the following image. The 'Unknown device' will need activating. You will be able to select it.
Emails should now be syncing successfully. If you continue to experience any problems, please contact HRS Support - firstname.lastname@example.org