Nov 24 2020 11:57 PM
we have users that sends email to O365 user mailbox, mail sending failed with error below
host contoso-com.mail.protection.outlook.com[xxx.xxx.xxx]said:451.4.7.500 server busy. please try again later from[xxx.xxx.xxx.xxx] (s777230)[HK2APC01FT138.EOP-APC05.PROD.PROTECTION.COM
any known fix?
Nov 25 2020 01:10 AM
Best open a support ticket.