O365 not able to work with SQL Server Database Mail

[cllee]

Hi,

I have a Win Server 2003, running SQL Server 2005. I wanted to configure email sending in SQL Server (Database Mail) using O365 with the following parameter:

- smtp.office365.com / 587
- basic authentication

I can ping to smtp.office365.com and telnet to port 587, but I hit the error while sending the mail:

Message
The mail could not be sent to the recipients because of the mail server failure. (Sending Mail using Account 1 (2020-03-05T10:31:22). Exception Message: Cannot send mails to mail server. (Failure sending mail.).
)

I tried with another SMTP host (without SSL), have no problem sending email .

Any idea where went wrong?

Thanks.

[#2]

@cllee STARTTLS - on ??

[#3]

@ankit shukla 
Where do i enabled STARTTLS? I don't see such option available.