> ## Documentation Index
> Fetch the complete documentation index at: https://cntillion.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Set up email forwarding

> Route Google Workspace, Gmail, Microsoft 365, Yahoo, or Proton mail to your agent

Forward incoming mail from your company address to the **Agent email** shown in
**Settings → Email**. Keep that page open while configuring your provider so you
can copy the exact destination and verify the rule afterward.

Forwarding setup does not enable AI replies. Enable them in the email channel
after checking your [plan and credit balance](https://cntillion.com/docs/workspaces/billing.md); automatic
email replies require Hobby or above.

A typical route is customer → `support@example.com` → your generated agent
address. Forward the original message automatically. Manually forwarding a copy
from your own mailbox does not prove that future customer mail will follow the rule.

## Google Workspace

Use **Default routing** in the Google Admin console when you administer a
Workspace domain. Routing can accept a support address without creating a
separate user mailbox for it.

1. Sign in to the [Google Admin console](https://admin.google.com/) as an administrator.
2. Open **Apps → Google Workspace → Gmail → Default routing**.
3. Choose **Configure** or add another rule.
4. Match the envelope recipient to the company address, such as `support@example.com`.
5. Choose **Change envelope recipient**, then **Replace recipient**. Enter the
   generated agent address copied from Centillion.
6. Apply the rule to **non-recognized and recognized addresses** if the support
   address should work whether or not a Workspace mailbox exists for it.
7. Save the rule.
8. Return to Centillion, choose **Verify automatic forwarding**, and check again
   after the verification message arrives.

Google routing changes can take up to 24 hours. Scope the rule to the support
address you are adding; a domain-wide rule would redirect other company mail too.

## Gmail mailbox forwarding

Use mailbox forwarding if you manage an individual Gmail inbox instead of
domain routing. For a Google Workspace address, your administrator may need to
allow forwarding first.

1. In Gmail on the web, open **Settings → See all settings → Forwarding and POP/IMAP**.
2. Choose **Add a forwarding address** and enter the generated agent address.
3. Google sends a confirmation to that address. Open the corresponding
   conversation in Centillion and use its code or confirmation link.
4. Return to Gmail and select **Forward a copy of incoming mail** to the verified
   destination. Choose whether to keep a copy in Gmail.
5. Save the changes. Adding and confirming the address alone does not turn forwarding on.
6. Return to Centillion and run the forwarding verification.

See Google's [forwarding instructions](https://support.google.com/mail/answer/10957)
for the current interface and account restrictions.

### Messages in Gmail spam

Gmail does not automatically forward messages it marks as spam. If a customer's
message is absent from Centillion, check Gmail's Spam folder first.

For a dedicated support inbox that should forward every incoming message, you
can add a Gmail filter under **Filters and Blocked Addresses**. A size rule of
**less than 200 MB** matches incoming Gmail messages. Select **Never send it to
Spam**, then create the filter. This changes Gmail's spam handling for that inbox;
turn on Centillion's [spam detection](https://cntillion.com/docs/channels/email.md#spam-detection-and-whitelisted-senders)
if you want suspected spam held for review after forwarding.

For a shared personal or mixed-purpose mailbox, use a filter limited to the
support recipient instead. Keep the original mailbox available while you test
that important customer messages reach Centillion.

## Outlook and Microsoft 365

For Outlook on the web or new Outlook, open **Settings → Mail → Forwarding**,
enable forwarding, and enter the generated agent address. Save the setting and
keep a copy of forwarded mail if your team needs one in Outlook.

Classic Outlook can use a rule instead. Follow Microsoft's
[automatic-forwarding instructions](https://support.microsoft.com/en-us/office/turn-on-automatic-forwarding-in-outlook-7f2670a1-7fff-4475-8a3c-5822d63b0c8e)
for your version. Prefer a server-side rule that continues to run when Outlook
is closed.

### Allow external forwarding for a work account

Microsoft 365 can block external automatic forwarding even when the mailbox
setting is enabled. A Microsoft 365 administrator must allow the support
mailbox to forward to the generated agent address.

1. Sign in to the [Microsoft Defender portal](https://security.microsoft.com).
2. Open **Email & collaboration → Policies & rules → Threat policies → Anti-spam**.
3. Open the outbound spam policy that applies to the support mailbox.
4. Edit its protection settings and set **Automatic forwarding rules** to
   **On: Forwarding is enabled**.
5. Save the policy and confirm that the mailbox is included in its scope.
6. Return to Centillion and run the forwarding check again.

A custom outbound policy can allow forwarding only for the support users or
groups. If your organization also restricts forwarding through Exchange remote
domains, ask the administrator to allow the generated address's domain there
as well. A remote-domain exception does not override an outbound spam policy
that blocks forwarding.

The error `5.7.520 Access denied, Your organization does not allow external forwarding`
means the organization is blocking the rule. Check the sender's non-delivery
report and ask the administrator to review the effective policy. See
[Microsoft's external-forwarding policy guide](https://learn.microsoft.com/en-us/defender-office-365/outbound-spam-policies-external-email-forwarding).

## Yahoo Mail

Automatic forwarding availability depends on your Yahoo account and plan.
Follow [Yahoo's forwarding guide](https://help.yahoo.com/kb/SLN22028.html).

1. Open Yahoo Mail's mailbox settings and locate forwarding.
2. Enter the generated agent address as the destination.
3. Complete any destination confirmation Yahoo sends. The confirmation arrives
   in your agent's conversations.
4. Enable and save the rule, then run Centillion's forwarding check.

If the forwarding control is unavailable, review the account's plan eligibility
or use a company mail provider that supports automatic routing.

## Proton Mail

Follow [Proton's forwarding guide](https://proton.me/support/email-forwarding)
for plan requirements and current restrictions.

1. Open Proton Mail's settings and find **Forwarding and auto-reply**.
2. Add a forwarding rule with the generated agent address as its destination.
3. Complete the destination confirmation sent to your agent's conversations.
4. Enable the rule and save it.
5. Return to Centillion and complete its forwarding verification.

Review Proton's explanation of encryption when forwarding outside Proton. Use a
supported company address for a custom sender; a `proton.me` address does not
give you control of that domain's DNS.

A Centillion Owner or Member must run the forwarding check in the agent
settings. Access to your mail provider alone does not grant permission to change
Centillion settings. See [workspace roles](https://cntillion.com/docs/workspaces/members.md).

## Finish in Centillion

Provider confirmation and Centillion verification are separate steps. First
confirm and enable the provider's rule. Then use **Verify automatic forwarding**
in **Settings → Email** so Centillion can check that a message reached the agent.

After forwarding passes, [authenticate the domain](https://cntillion.com/docs/channels/email-dns.md) and
choose the address in the email channel. Each additional address needs its own
forwarding rule and check, even on an already authenticated domain.

Test a forwarded message with an attachment as well as a plain-text message.
Forwarded files use the [email attachment limits](https://cntillion.com/docs/channels/email.md#attachments-and-threading),
and files the agent cannot read need your team's review.

For human handoff, open **Tools** and create or edit a **Create ticket** action.
Include **Email** in its channels and save and enable it. If your team answers
in Zendesk, follow [Zendesk email handoff](https://cntillion.com/docs/helpdesk/zendesk-email.md) to connect
that destination and test ticket creation and replies.

## When verification does not pass

* Copy the generated destination again and check for a typo or an old agent address.
* Confirm the rule is enabled, not just saved as a possible destination.
* Approve any verification message from the provider in the agent's conversations.
* Check rules that move, delete, or reject messages before forwarding.
* For Gmail, inspect Spam. For Microsoft 365, check the external-forwarding policy.
* Allow time for provider changes, then start a fresh check if the previous one expired.

Do not forward the generated agent address back to the company mailbox. That
creates a loop. The company address should forward into Centillion, and
Centillion sends the reply to the customer.


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