# Setting up Email Auto Forwarding (Outlook/Microsoft)

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Setting up Email Auto Forwarding (Outlook/Microsoft). Auto-forwarding sends your client's emails to Briefcase automatically. Briefcase picks out the individual.

Auto-forwarding sends your client's emails to Briefcase automatically. Briefcase picks out the individual transactions and puts them into your client's Briefcase inbox, handling duplicate checks and multi-page invoice splits along the way.

**There are two ways to set this up:**

-   **Forward everything** → you have direct access to the client's inbox and want all of its email forwarded to Briefcase.

-   **Forward specific senders** → you receive emails from several clients in one shared inbox and want each client's emails forwarded to their own Briefcase account.

You'll find the client's Briefcase forwarding address (ending in **@briefcase.to**) in the client's **Business Settings** in Briefcase.

### Option A: Forward everything

**Outlook for Windows**

1.  On the **Home** tab, click **Manage Rules & Alerts**, then **New Rule**.

2.  Under "Start from a blank rule", select **Apply rule on messages I receive** and click **Next**.

3.  Leave the conditions empty and click **Next**, then click **Yes** to apply the rule to every message.

4.  Select **forward it to people or public group**, click the underlined **people or public group**, enter the client's Briefcase forwarding address, and click **OK**.

5.  Click **Next** past the exceptions (leave them empty), then click **Finish**.

6.  Name the rule (e.g. **\[Client Name\] - Briefcase Auto Forwarding**) and click **OK**.

**Outlook for Mac**

1.  On the **Message** tab, click **Rules**, then **Edit Rules**.

2.  Click **+** to add a rule and name it (e.g. **\[Client Name\] - Briefcase Auto Forwarding**).

3.  Set the condition to **Apply to all messages**.

4.  Set the action to **Forward to** and enter the client's Briefcase forwarding address.

5.  Click **Save**.

***All emails received in this inbox will now be forwarded to your client's Briefcase inbox.***

### Option B: Forward specific senders (multiple clients)

Create one rule per client that matches that client's sender addresses.

**Outlook for Windows**

1.  On the **Home** tab, click **Manage Rules & Alerts**, then **New Rule**.

2.  Select **Apply rule on messages I receive** and click **Next**.

3.  Tick the condition **from people or public group**, click the underlined **from people or public group**, and enter the sender addresses belonging to one client. Click **Next**.

4.  Select **forward it to people or public group**, click the underlined **people or public group**, enter that client's Briefcase forwarding address, and click **OK**.

5.  Click **Next** past the exceptions (leave them empty), then click **Finish**.

6.  Name the rule (e.g. **\[Client Name\] - Briefcase Auto Forwarding**) and click **OK**.

7.  Repeat for each client.

If your inbox receives mail for several addresses, also tick the condition **to people or public group** in step 3 and set it to the address your clients email (e.g. your internal receipts@ address).

**Outlook for Mac**

1.  On the **Message** tab, click **Rules**, then **Edit Rules**.

2.  Click **+** to add a rule and name it (e.g. **\[Client Name\] - Briefcase Auto Forwarding**).

3.  Set the condition to **From** and enter that client's sender addresses (e.g. admin@, invoices@, finance@).

4.  Set the action to **Forward to** and enter that client's Briefcase forwarding address.

5.  Click **Save**.

6.  Repeat for each client.

***Emails will now be forwarded to each client's Briefcase inbox based on your rules.***

### Troubleshooting: "Your organization doesn't allow external forwarding"

If Outlook shows **"Your organization doesn't allow external forwarding. Please contact your administrator for further assistance"** when your rule tries to forward, the block is coming from **Microsoft 365** — not from Briefcase. Since 2020, Microsoft blocks automatic external forwarding by default through its outbound anti-spam policy, so a Microsoft 365 administrator needs to allow forwarding to Briefcase.

These changes must be made by a **Microsoft 365 / Exchange administrator** — the person creating the forwarding rule can't fix this from Outlook. If that isn't you, forward the steps below to your IT team.

**Step 1 — Allow automatic forwarding for the mailbox**

We recommend scoping this to only the mailbox(es) that forward into Briefcase, so the rest of your organisation stays locked down.

1.  Go to the **Microsoft Defender portal** ([security.microsoft.com](https://security.microsoft.com/)).

2.  Open **Email & collaboration → Policies & rules → Threat policies → Anti-spam**.

3.  Click **Create policy → Outbound**.

4.  Give it a name (e.g. *Allow Briefcase forwarding*) and, under **Users, groups, and domains**, scope it to the mailbox(es) that forward into Briefcase.

5.  Under the protection settings, set **Automatic forwarding rules** to **On – Forwarding is enabled**.

6.  Click **Save**. Changes can take up to an hour to take effect.

**Step 2 (optional) — Restrict forwarding to Briefcase only**

Step 1 lets those mailboxes forward anywhere. To allow forwarding **only** to Briefcase and keep every other external destination blocked, add a mail flow rule:

1.  Go to the **Exchange admin center** ([admin.exchange.microsoft.com](https://admin.exchange.microsoft.com/)) → **Mail flow → Rules → Add a rule → Create a new rule**.

2.  Under **Apply this rule if**, choose **The message properties → include the message type → Auto-forward**.

3.  Add an exception: **Except if → The recipient → address matches any of these words**, and enter **briefcase.to**.

4.  Under **Do the following**, choose **Block the message → reject the message and include an explanation**.

5.  Click **Save**.

The result: auto-forwards to **@briefcase.to** are allowed, and auto-forwards to any other address stay blocked. Every Briefcase forwarding address ends in **@briefcase.to** (for example *acme-limited-4821@briefcase.to*), so allowing that one domain is all you need.

You may see advice to simply add a **Remote Domain** for briefcase.to. In current Exchange Online the outbound anti-spam policy overrides remote-domain settings, so **Step 1 above** is what actually clears this error — the remote-domain setting alone will not.

If the block persists after these changes, ask your admin to check for a custom mail flow (transport) rule that blocks external forwarding, under **Exchange admin center → Mail flow → Rules**.

### Good to know

-   Send a test email after setup to confirm forwarding is working.

-   If you see **"Your organization doesn't allow external forwarding"**, follow the Troubleshooting section above. If you don't see the rule options at all, contact your IT support.

-   Using Gmail instead? See [Setting up Email Auto Forwarding (Gmail)](https://briefcase.so/articles/setting-up-email-auto-forwarding-gmail).

-   Using an email client other than Outlook or Gmail? Email us at [support@briefcase.so](mailto:support@briefcase.so) and we'll help you get set up.