Errors while sending test email

Your software
My Mautic version is: bitnami-mautic-3.3.3-5-r02
My PHP version is: 7.3.28
My Database type and version is: mysqlnd 5.0.12-dev

Your problem
My problem is:

My instance is created on AWS EC2 and SMTP Service is from office365. I have done all the configuration on office365 and on AWS. Also get AWS approve to remove the limit on SMTP Port.

My test connection provide successful status however when trying to send test email getting the below error.

I consult with Microsoft, AWS & with Bitnami support but not able to find solution so I was asked to check on this form as your issue will be sorted out.

Please advise if you need any additional information to investigate on this issue.

Error:
Expected response code 354 but got code “503”, with message "503 5.5.1 Bad sequence of commands "

These errors are showing in the log: On Mautic appilcation itself

Steps I have tried to fix the problem: None

Hello,
I think you have a port issue.
Check this cvonversation:

However this is rather an Outlook problem then Mautic. You’ll find more info in the Outlook forums I think.

Joey

I already gone through this link and followed the same on Mautic to connect the office365 SMTP which provide successful test connection but won’t sent test email.