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Microsoft 365: connect and send an e-mail

5 steps± 4 minVideoVerified 22 Oct 2026
  1. Step 1 · Open your development environment
  2. Step 2 · Choose Microsoft 365
  3. Step 3 · Fill in the app registration and test
  4. Step 4 · Use the building block Outlook · Send email
  5. Step 5 · Save, run and check

A connection with Microsoft 365 gives workflows and AI Colleagues building blocks for Outlook mail and calendar, Teams and OneDrive/SharePoint. You connect an app registration from Microsoft Entra ID, test the connection and send an e-mail with the building block Outlook · Send email. You need: the tenant ID, client ID and client secret of an app registration with the application permission Mail.Send.

Watch the whole guide as a video5 steps in one film
Step 1 / 5

Open your development environment

In the portal, under Environments, click Development, and there Open. Flow opens in a new tab and you are signed in straight away.

  1. Click Development
Open your development environment · Click Development
  1. Click Open ↗
Open your development environment · Click Open ↗
Step 2 / 5

Choose Microsoft 365

Under Connections you choose Microsoft 365. On the right is what to arrange in Microsoft Entra ID, and per building block which permission it needs: grant only what you use. Sending needs Mail.Send.

  1. Click Connections
Choose Microsoft 365 · Click Connections
  1. Click Microsoft 365
Choose Microsoft 365 · Click Microsoft 365
Choose Microsoft 365 · Outlook · Send email needs Mail.Send.
Step 3 / 5

Fill in the app registration and test

Works as App: Flow works in the background, without anyone signed in, on behalf of the default mailbox. The client secret is stored encrypted and can never be read back. Choose Read and write, because sending changes something. Save and test asks Microsoft for an access token straight away.

  1. In Name, type Outlook · support@
  2. In **Tenant ID ***, type fietsenmakerdewit.onmicrosoft.com
  3. In **Client ID ***, type 7c1e2b9a-4d3f-4a8e-9b6c-2f5d8e1a3c47
  4. In **Client secret ***, type ••••••••
  5. In Default mailbox, type support@dewitbikes.com
Fill in the app registration and test · In Name, type Outlook · support@; In **Tenant ID ***, type fietsenmakerdewit.onmicrosoft.com; In **Client ID ***, type 7c1e2b9a-4d3f-4a8e-9b6c-2f5d8e1a3c47; In **Client secret ***, type ••••••••; In Default mailbox, type support@dewitbikes.com
  1. Click Read and write
Fill in the app registration and test · Click Read and write
  1. Click Save and test
Fill in the app registration and test · Click Save and test
Fill in the app registration and test · Connection works: Microsoft handed out a token. Below it you see which permissions are still missing.
  1. Click Cancel
Fill in the app registration and test · Click Cancel
Fill in the app registration and test · The connection: Read and write, key stored, just tested.
Step 4 / 5

Use the building block Outlook · Send email

Create a workflow and add Outlook · Send email from the library. Choose your connection, fill in To, Subject and Message. Leave Mailbox empty: Flow then sends from the connection's default mailbox. Every field may contain {{variables}}, such as a customer's address from an earlier step.

  1. Click Add to General
Use the building block Outlook · Send email · Click Add to General
  1. Click New workflow
Use the building block Outlook · Send email · Click New workflow
  1. In Workflow name, type Confirmation by mail
Use the building block Outlook · Send email · In Workflow name, type Confirmation by mail
  1. Click Add node
Use the building block Outlook · Send email · Click Add node
  1. In Search a node, type Outlook
Use the building block Outlook · Send email · In Search a node, type Outlook
  1. Click Outlook · Send email
Use the building block Outlook · Send email · Click Outlook · Send email

Your bike is done and waiting for you in the shop.

Kind regards, De Wit Bikes`

  1. In Connection, choose Outlook · support@
  2. In To, type john.smith@example.com
  3. In Subject, type Your bike is ready · 1792645493
  4. In Message, type `Good afternoon,
Use the building block Outlook · Send email · In Connection, choose Outlook · support@; In To, type john.smith@example.com; In Subject, type Your bike is ready · 1792645493; In Message, type `Good afternoon,
Use the building block Outlook · Send email · ‘Changes something in Outlook’: this building block writes.
  1. Click the dot of ‘Event trigger’
Use the building block Outlook · Send email · Click the dot of ‘Event trigger’
  1. Click the dot of ‘Outlook · Send email’
Use the building block Outlook · Send email · Click the dot of ‘Outlook · Send email’
  1. Click the step ‘Event trigger’
Use the building block Outlook · Send email · Click the step ‘Event trigger’
  1. Click Align horizontally
Use the building block Outlook · Send email · Click Align horizontally
Step 5 / 5

Save, run and check

At the bottom you see that the step stored its result: sent, from which mailbox, to whom. In Outlook the mail is then in the mailbox's Sent Items.

  1. Click Save
Save, run and check · Click Save
  1. Click Run
Save, run and check · Click Run
Save, run and check · The mail was sent; the result is in the run's data.
Save, run and check · The recipient in the run's data.

This guide was carried out step by step on 22 Oct 2026 by an automated test on Flow (version 3e563176).