How to check basic authentication logs

Question

Hi Experts

I am setting POP3 authentication on a printer to receive emails in it and then print the emails automatically.

I know that the basic authentication for Exchange Online has been disabled, but the question is, when I finished configuration on the printer (POP3/SSL/995/username/password), and set it to fetch email every 15 minutes, I can't see any sign-in logs in Azure Admin-Users-sign-in logs.

1. I can see the traffic were allowed in the firewall: outbound port 995 every 15 minutes.
2. The printer supports OAuth2.0, and it works good on it.

So the connectivity to POP3 server: outlook.office365.com is good. (While for some reason, we can't use OAuth2.0)

1. The email account has enabled MFA, and has license.

My concern is why there isn't any sign-in logs on Azure. I think there should be some "fail" logs every 15 minutes because the printer will try to contact the POP3 server every 15 minutes.

I set the filter but no use, as there isn't any logs to filt...

Thank in advance

Answer 1

Basic authentication is being blocked on the pre-authentication layer in Exchange Online, so the request never hits Azure AD, and thus you will see no sign-in logs therein.