If you receive this bounce back message after configuring server-side setup for MIcrosoft 365 then you must add Xink's SPF record in your DNS.
Solution: Proceed to ---> IT Pro: Adding SPF records
If you receive this bounce back message after configuring server-side setup for MIcrosoft 365 then you must add Xink's SPF record in your DNS.
Solution: Proceed to ---> IT Pro: Adding SPF records