> ## 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. # AI email support agent > Let your agent answer support email from a generated address, a forwarded company address, or a connected Gmail or Outlook inbox. Set up and test it. Your AI email support agent answers mail sent to its generated address, mail forwarded from your company addresses, or mail in a connected Google or Microsoft inbox. Replies stay in the customer's email thread, and your team can step in at any point. ![Email card on the Channels page with a connected Helpdesk address, its Automatic replies switch and Connect another account](https://mintcdn.com/centillion/OVR3XViKbG9zMitv/images/channels/email-01-channel-card.webp?fit=max\&auto=format\&n=OVR3XViKbG9zMitv\&q=85\&s=afe4064f184cca412f0d0c4bf7bbaa6e) The Email card on the Channels page connects an existing inbox. ## What it does * Receives email in one of three ways: a generated agent address, a company address that forwards to it, or a connected Gmail or Outlook inbox. * Replies in the same thread, keeping the subject and threading headers, from the address the customer wrote to when it is one you selected. * Reads attached images and the text of PDF, DOCX, plain text, Markdown and CSV files, up to five files of 5 MB each for an automatic reply. * Holds suspected spam, skips mailing lists and automatic mail, and never answers blocked senders. * Waits up to one hour before sending, if you set a reply delay, and pauses when a person takes over from the [helpdesk inbox](https://cntillion.com/docs/helpdesk.md). ## What you need * The Owner or Member role. Viewers can inspect the settings and preview email formatting without saving. See [workspace roles](https://cntillion.com/docs/workspaces/members.md). * A plan with automatic email replies: Hobby and up. The Helpdesk inbox your team works from comes with Standard and up. * For the generated agent address: an enabled Helpdesk and an available email service. * For a company address with forwarding: access to the mailbox or its mail routing settings, plus the domain's DNS. * For a connected inbox: permission to authorise read and send access to a Google or Microsoft mailbox. Choose a dedicated support inbox. ## Set it up Pick the setup that matches where your support mail lives. Each ends with the same test: a message from an outside mailbox that appears under **Conversations** and gets a reply. ### The generated agent address **1. Open Settings, Email** Open your agent's **Settings**, then **Email**. Opening the page sets up Helpdesk and the generated address for an agent that has none yet, with automatic replies paused. If Helpdesk was switched off, choose **Enable email channel**. ![Settings Email tab with a Generated address unavailable notice and the Email configuration card](https://mintcdn.com/centillion/hWC-069gfv-5h1TN/images/channels/email-02-settings-page.webp?fit=max\&auto=format\&n=hWC-069gfv-5h1TN\&q=85\&s=06efefe18062d43cc1b3b6630edd40e9) Settings, Email shows generated-address availability and configuration for your own domain; this demo has no receiving service connected. **2. Turn on automatic replies** Open **Playground**, choose **Email**, then **Configuration**, and enable **Automatic replies**. **3. Send a test** Write to the generated address from an external mailbox. Check that the message appears in **Conversations** and receives a reply. ### A company address with forwarding **1. Add the address and forward it** Add your support address in **Settings**, **Email**, and set up a forwarding rule in your mailbox that sends its mail to the generated address. [Email settings](https://cntillion.com/docs/channels/email-settings.md) walks through it. **2. Verify forwarding and authenticate the domain** Verify forwarding for each address, even if its domain is already authenticated, then add the DKIM and SPF records. The page shows each check, and DMARC status too. A saved address is not proof that its forwarding or DNS works. **3. Select it as a reply address** Open **Channels**, find **Email**, and choose **Manage**. Select the ready address under reply addresses and save. Then enable **Automatic replies** and send a test to the company address. If mail never reaches Centillion, read the [forwarding guide](https://cntillion.com/docs/channels/email-forwarding.md). If the custom sender is not ready, read the [DNS guide](https://cntillion.com/docs/channels/email-dns.md). ### A connected Gmail or Outlook inbox **1. Connect the mailbox** Open **Channels**, find **Email**, and choose **Connect email**. Continue with Google or Microsoft and authorise the support mailbox. Your organisation's administrator may need to approve access. No forwarding rule or DNS change is needed. **2. Review the settings** Connected inboxes start with automatic replies paused. Review the email settings while they are. **3. Enable replies and test** Enable automatic replies for the inbox the agent should answer, then send a test from another mailbox. Only messages in the inbox folder are answered. Mail your provider or rules move elsewhere is left alone, and mail that arrived before you enabled automatic replies is not answered. Shared Microsoft mailboxes and sending aliases are not separate account choices. If the connection shows **Needs attention**, read the error and reconnect: an administrator can revoke access even when the inbox worked before. ## Use it every day Open **Channels**, **Email**, **Manage**, or the Playground with **Email** selected. Both edit the same configuration, so saving in the Playground changes the live channel; use a test agent to try settings safely. * **Reply addresses.** When a customer writes to a selected address, the reply comes from that address. Otherwise it comes from the first selected address, or from the generated address when none is selected. A connected inbox sends through the mailbox you authorised. * **Email display name.** The sender name beside the address, such as `Acme Support`. It changes the name, not the authenticated address. For teammate replies, [Helpdesk email settings](https://cntillion.com/docs/helpdesk/email-settings.md) can use the responder's name or a fixed team name. * **Deliverability alert contact.** An active team member who gets alerts about recipient-server delays, bounces, spam complaints or failed delivery. **None** turns them off. Saving the contact sends no test alert. Alerts work for a connected inbox even with Helpdesk off; pick a member with an email address who can investigate. * **Blocked senders.** Complete addresses that never get an automatic reply. Their messages stay in conversations, and changes apply to future mail. Type an address and press **Enter**, comma or semicolon, or paste several at once. Each becomes a chip you remove with **×**; duplicates appear once. * **Spam detection.** Holds suspected spam without replying. Your team can reply by hand or choose **Reply anyway**. Whitelisted senders skip the spam check, but not the block list or the reply-loop checks. Turning detection off keeps the whitelist. * **Reply delay.** Seconds or minutes, up to one hour. Zero or empty sends at once. The agent prepares the answer on arrival and holds delivery; a pending reply shows its remaining wait. Taking over cancels waiting replies, and the customer never sees them. Team replies and **Reply anyway** send at once. * **AI composition disclaimer.** Marks automatic replies, by default with `This message is composed by AI.` You can change the wording. Teammate replies never carry it. * **Signature.** A formatted signature with links, lists, text styles and contact details. A saved Helpdesk signature takes precedence for AI replies; when it is empty, AI replies use this one while its switch is on. Teammate replies use the Helpdesk signature. Switching it off keeps the draft; clearing the editor and saving deletes it. To remove signatures from both kinds of reply, clear the Helpdesk signature and turn off or clear this one. Keep it short enough to read on a phone. The Playground's Email preview is a static sample of an outgoing email: From name, address, signature, disclaimer and footer. It has no composer, does not generate an answer or send email, and does not check forwarding or DNS. Use **Chat bubble** to try answers (the **Preview** and **Install** buttons appear only there), then send a real test email. Actions that send messages or create tickets need a real channel test too; see [Troubleshooting](https://cntillion.com/docs/troubleshooting.md). When your team takes over a conversation, replies pause. Choose **Allow AI replies** in the ticket when the agent should answer again. ### Hand email conversations to Zendesk A **Create ticket** action with **Zendesk** as its Helpdesk destination creates a Zendesk ticket and pauses automatic replies on that email thread. Your team answers in Zendesk. A **Solved** or **Closed** ticket resumes the original conversation unless a newer manual takeover is active. See [Zendesk email handoff](https://cntillion.com/docs/helpdesk/zendesk-email.md) to connect the account, configure the action, and test ticket creation, customer follow-ups, and resumption. The Email Playground does not run a handoff. ## Limits and good to know * **Addresses and domains.** Up to 3 custom email domains per workspace and 20 addresses per domain, counting all of the workspace's agents. * **Incoming files.** Helpdesk keeps up to 5 attachments per email, 25 MB per file and 125 MB combined. Automatic AI replies support up to 5 files of 5 MB each. PDFs are limited to 5 pages and 2,000 tokens per page, and document text to 30,000 characters per email. Unsupported or omitted files, scanned or unreadable PDFs, and documents over the limit pause the AI reply for your team. Use a model that accepts images if customers send pictures. An email can carry an attachment with no body. Test the file types your customers use through the real configured address; your team can attach files to replies from Helpdesk too. * **Mail the agent skips.** Mailing lists, bulk mail, automatic replies, out-of-office messages, common no-reply addresses such as `mailer-daemon@` and `postmaster@`, blocked senders, mail you sent yourself, and mail from another generated Centillion Helpdesk address. * **Delivery failures.** Centillion retries a failed send. A reply that still cannot be sent stops retrying, and the alert contact is told. * **Formatting.** Replies keep their Markdown formatting in the HTML email, including text inserted from Helpdesk macros. Plain-text readers get the same content without formatting. * **Branding.** The **Powered by Centillion** footer is hidden on automatic replies, teammate replies, new Helpdesk emails and previews once the white-label add-on is active; the signature and disclaimer keep their own settings. Owners buy and manage it in **Workspace settings**, **Billing**; see [Plans and billing](https://cntillion.com/docs/workspaces/billing.md). * **Campaign links.** Email replies keep their original link destinations. Visitors who reach your site from an email campaign keep their UTM parameters on agent links through the [script embed](https://cntillion.com/docs/channels/utm-tracking.md). ## Questions ### Which of the three setups should I choose? Use a connected inbox if your support mail already lives in Gmail or Outlook: it needs no forwarding or DNS. Use a company address with forwarding if customers already write to an address on your domain and should get replies from it. The generated address alone is the quickest way to test. ### Why did a test email get no reply? Check that **Automatic replies** is on, that the sender is not blocked, and that the message was not held as spam. A connected inbox answers only mail in the inbox folder that arrived after you enabled replies. ### Can customers see that a reply was written by AI? Only if you enable the AI composition disclaimer. It is added to automatic replies and never to replies your team writes. ### What happens when my team takes over? Waiting automatic replies are cancelled and the conversation pauses. Your team replies from the ticket, and **Allow AI replies** hands it back to the agent. ### Before I use a company address with customers, what should I test? Send a new email, check the AI reply, send a follow-up in the same thread and take over as a teammate. Check the From name, address, signature and disclaimer in the received mail, and try blocked senders, spam and the reply delay with accounts you control. ### Can the same agent answer chat and phone too? Yes. One agent answers on every channel you connect; see [What Centillion is](https://cntillion.com/docs/introduction.md). ## Try it Write to your agent's generated address from your own mailbox. The reply lands in the same thread, and the conversation shows up in the dashboard. > [card] [Start free](https://app.cntillion.com/sign-up?utm_source=docs\&utm_medium=article\&utm_campaign=channels-email) > > Start on the Free plan, or take a seven-day trial of a paid plan. Your agent is live on your site in an afternoon. > [card] [Book a demo](https://cal.com/patrick-turricelli-smgfks/15min?utm_source=docs\&utm_medium=article\&utm_campaign=channels-email) > > Fifteen minutes with the team, on your own use case. Or ask the assistant on this page. ## Related > [card] [What Centillion is](https://cntillion.com/docs/introduction.md) > > The product in one page: agents, knowledge, channels and the helpdesk. > [card] [Helpdesk](https://cntillion.com/docs/helpdesk.md) > > Where your team takes over email threads and replies. > [card] [Email forwarding](https://cntillion.com/docs/channels/email-forwarding.md) > > Forward a company address to your agent and verify the route. This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.