Email succesfully sent but not appear in Sent Items (Microsoft 365)

Question

Hi Good day to everyone here.

My first questions, here we go but i'll try to explain it the best way I could.

I develop auto sending email features using javaxmail in my application for my customer. Previously when using setting smtp.office365.com I able to send email and the copies of sent email are display in Sent Items folder.

Recently when there are hiccup with smtp office (time out frequently), the IT department at my customer change the setting to use local server instead for smtp (with ip address 172.162.etc.etc). However since the start using this new setting, the email no longer appear in Sent Items but the email still able to sent out ( I test sending email to myself and able to received it ).

Since Im not really familiar and have very limited knowledge on server side for mail server, is there anything I can suggest to the IT department to check for? I only can login the email account on web (https://outlook.office.com/mail/) but when using outlook it required authentication. With web mail i already go thru all settings available and didn't see anything related.

Thanks in advance. Sorry if the question confusing and misleading.

Answer 1

Well, of course - your local SMTP server knows absolutely nothing about your remote Exchange mailbox. It cannot possibly place anything in your Sent Items folder.

You need to send using your Exchange Server - its SMTP server does place sent messages in the Sent Items folder owned by the authenticated user. Keep in mind that MS has recently disabled basic auth in M365. You need to re-enable it for your tenant and the particular mailbox used to send messages.