Prerequisites
The connector should already be set up, with a Connector Profile and a Linked Account. See Getting Started on the Microsoft Outlook connector page.How StackOne sets up Microsoft Outlook webhooks
Nothing needs configuring in Outlook or Azure. When you connect an account with events enabled, StackOne creates a Microsoft Graph change-notification subscription automatically and deletes it again when the connection is removed. A single subscription carries every event you enable.
Check that the mail permission is granted
A message subscription needs read access to mail — Mail.ReadBasic is enough, and Mail.Read or Mail.ReadWrite satisfies it too. No webhook-specific permission has to be added.
- If the connection can list messages today, it can receive mail webhooks.
- Microsoft Graph rejects write-only access — a read permission is required even though the subscription only reads data.
Check which mailbox is covered
The subscription is created against the mailbox of the user who authorised the connection, so it reports changes to that user’s messages only. To follow another user’s mail, connect an account authorised by that user.
- The whole mailbox is covered, not just the Inbox — drafts, Sent Items and folder moves all raise events.
Connect the account again when the subscription expires
Microsoft Graph expires mail subscriptions after at most seven days, and StackOne does not renew them. Delivery stops silently when the subscription lapses — no error is raised, events simply stop arriving.
- Reconnect the account to create a fresh subscription and resume delivery.
- Reconnecting also removes the previous subscription, so no duplicates are left behind.
Available webhook events
Microsoft Outlook emits three event types, covering the lifecycle of a message in the connected user’s mailbox. Only events selected in StackOne are dispatched to your application.
Enable message events
Events covering messages anywhere in the connected user’s mailbox. Because the whole mailbox is covered, mail the user sends or drafts raises the same events as mail they receive from others.
- Message Created (
message_created) — Fired when a message is added to the mailbox: mail received, a draft saved, or a sent message filed into Sent Items. - Message Updated (
message_updated) — Fired when a message changes, including marking it read or unread, changing a flag or category, editing a draft, or moving it between folders. - Message Deleted (
message_deleted) — Fired when a message is removed from the mailbox.