Outlook · calendar and mail
Outlook integration: calendar and mail in your app
Outlook integration means an action in your system creates a calendar event or puts a mail in the user’s Outlook — via Graph, not via an SMTP hack from your server with a shared password. “Book follow-up” writes in the seller’s calendar. Case mail is sent from the user’s own mailbox so replies land in the right place. Read only what you need to show “last activity”. Mirroring the whole inbox into your UI is building a worse Outlook. Delegated when the action is on behalf of a user. App-only when a service job runs without a person. Do not mix them at random. The hub is [Microsoft 365](/articles/integrations/microsoft-365-integration).
Notifications people already sit in can belong in Teams instead of yet another mail. Automation on top of the calendar you have.
What gives value
- “Book follow-up” writes in the seller’s calendar
- Case mail is sent from the user’s own mailbox so replies land in the right place
- Read only what you need to show “last activity”
Delegated
- The action is on behalf of a user
- The meeting lands in their calendar
- The mail comes from them
App-only
- A service job without a person
- Needs admin consent and tight scopes
- Do not mix it at random with delegated
What to do now
Point to one button: book a meeting or send case mail. Not both plus “read the whole inbox”. That is how the scope holds.
FAQ about Outlook integration
App-only or delegated?
Delegated when the action is on behalf of a user. App-only when a service job runs without a person. Do not mix them at random.
Can we send via SMTP with a shared password?
Do not. Graph with delegated or a real shared mailbox. A shared password is a hole you dug yourselves.
Must we show the whole calendar in the app?
No. Show the event the case created, and a link to Outlook.
What about a Teams meeting link?
That is Graph + Teams, not “Outlook alone”. Spec it as part of the meeting flow. See Teams integration.