Unable to configure the emailgtw probe settings using an Office365 SMTP server.
"Test" option in emailgtw probe SMTP menu fails and produces the following error in the emailgtw.log:
emailgtw: EHLO %MachineNameOfemailgdtwProbe%.domain.com
emailgtw: 250-%<server>.office365.com% Hello [ xxx.xxx.xx.xxx.xxx]
emailgtw: 250-SIZE 157286400
emailgtw: 250-PIPELINING
emailgtw: 250-DSN
emailgtw: 250-ENHANCEDSTATUSCODES
emailgtw: 250-AUTH LOGIN XOAUTH2
emailgtw: 250-8BITMIME
emailgtw: 250-BINARYMIME
emailgtw: 250 CHUNKING
emailgtw: (cmd_test_smtp_login) smtp_open succeeded
emailgtw: AUTH LOGIN
emailgtw: 334 VXNlcm5hbWU6
emailgtw: (test_login) getting username and password for host xxx.xxx.xx.xxx.xxx]
emailgtw: xxxxxxx - found match [ xxx.xxx.xx.xxx.xxx]
emailgtw: <suppressed>
emailgtw: 334 UGFzc3dvcmW6
emailgtw: <suppressed>
emailgtw: 535 5.7.3 Authentication unsuccessful [%<server>.<domain>.outlook.com]
Here are some helpful links to troubleshoot this problem:
1. Use Telnet to verify SMTP communication outside of the emailgtw probe
How to Use Telnet to Test SMTP Communication
https://technet.microsoft.com/en-us/library/aa995718
2. See the following link with a solution for the "535 5.7.3" SMTP error:
https://answers.microsoft.com/en-us/msoffice/forum/msoffice_o365admin-mso_dep365/smtpoffice365com-relay-535-573-authentication/9de8d176-1c07-4e66-b14f-148d3bd51bbf.