A copy in Sent Items, even for a shared mailbox

Updated: July 2026

You send on behalf of a shared mailbox (billing, support, contact) through an SMTP relay or Direct Send, and nothing shows up in Sent Items. No one sees what went out, you cannot re-read, prove, or reply from the history. It is a known Microsoft 365 limitation.

Why the copy is missing

An SMTP relay, Direct Send and High Volume Email hand the message to Microsoft for distribution but drop nothing in the sender's mailbox. Even the Graph API only saves the copy if you explicitly ask for it (saveToSentItems). A classic application send does not, so the trace disappears, especially for a shared mailbox that several people need to follow.

The fluctuat solution

fluctuat sends each message through the Graph API within your own Microsoft 365, as the real sender, and drops the copy in its Sent Items, including for a shared mailbox. Your applications do not change: they speak SMTP as today, you simply replace the outgoing server with your fluctuat endpoint. The permission granted is Mail.Send only.

The result: every automated send leaves a trace where your team looks for it, in the Sent Items of the mailbox concerned.

Frequently asked

Does it work for a shared mailbox with no dedicated licence? Yes, as long as the address exists in your tenant and you authorize sending as it.

Do we need Send As rights on the Microsoft side? You stay in control: an Application Access Policy can limit it to the exact set of mailboxes you want.

Create an account, first send in ~15 min

Free to start, no card. A Sovereign edition is available for sending that never transits through Dizzus.