If you have configured remote domains between your organization and other organizations to customize settings such as the ...

If you have configured remote domains between your organization and other organizations to customize settings such as the type of encoding to use, whether non-delivery reports are enabled, the character set to use, and so on, you should re-create similar custom remote domains in your %BRAND_OFFICE_365_SHORT% organization. Learn more at Remote domains in %BRAND_EXCHANGE_ONLINE_SHORT% Online.