Unable to connect to Microsoft as custom account

[Bill_Adams]

I am trying to add a MS O365 email address to the 'Connect custom email'.   I keep getting the error "Your connection was unsuccessful - Unfortunately Jira couldn't connect (blah) mail server said: "AUTHENTICATE failed."

I have disabled/re-enabled the email request option.

I have confirmed MFA is not enabled.   

I have logged into this account with a browser, using incognito/private browsing multiple times to OWA.      

I have reset the account password and tried again.   Browser works, JIRA connect does not.

We do have the 'block legacy authentication' enabled from within O365, which would disable (IMAP, POP, SMTP)

However, we are trying to use the 'Microsoft' connector, which hopefully uses OWA or Exchange Active Sync??   

Last - It is a pretty standard account name "TestITSupport@mycompany.net" which is 100% O365 online with no on-premise infrastructure, no on-premise firewalls...etc.   We are a cloud-only solution.

Thanks

NOTE - Updated at 10:52 with some new info. 

[Angélica Luz]

Hello Bill,

Welcome to Atlassian Community!

Checking the logs for your site, I didn't find any other error that could help us identify what is causing this issue.

As a test, can you please try connecting the email using the option "Other" instead of Microsoft?

You can use the details below:

Mail server: outlook.office365.com
Protocol: IMAPS
Port: 993

Also, make sure that IMAP is enabled for the account and if you are using Azure, the option "Enable security defaults" must not be enabled for your site. This option usually blocks IMAP and POP connections.

• What are security defaults?

Regards,
Angélica