My company has Office 365.
We use account for send email (SMTP/SSL) https://www.gmass.co/blog/office365-smtp/#office
We get error similar like this, but using Exchange Online https://docs.microsoft.com/en-us/answers/questions/817963/error-in-processing-451-470-temporary-server-error.html
We get the error:
Error in processing. 4.3.111 Temporary server error. Please try again later MRH1 [Hostname=PA4PR04MB9341.eurprd04.prod.outlook.com]
it is intermittent.
Any suggestions for troubleshooting ?
Updated:
Support recomended:
1- Check concurrent connections (max 3) and how much applications use the email account for sending.
https://docs.microsoft.com/en-us/exchange/troubleshoot/send-emails/smtp-submission-improvements
2- Check sending limits for Exchange on line.
• 30 messages per minute
• Recipient rate limit of 10,000 recipients per day
3- Check that source IP has SPF register
4- Check TLS version using by the app. Must be 1.2 version. Other case, enable the parameter for TLS versions older.
- Set AllowLegacyTLSClients from cmdlet Set-TransportConfig to "True"
- Older clients and apps must be configured using endpoint smtp-legacy.office365.com