Mail Sending Settings — Delivery Modes & Helpdesk Address

Mail Sending Settings — Delivery Modes & Helpdesk Address

What Is the Sending Screen?

The Sending screen controls how Horizon delivers outbound emails — which address emails appear to come from, and whether they're sent through Horizon's mail infrastructure or your own mail server.

You'll find it at Admin Panel → Integrations → Mail → Sending.

Key Concepts

  • Helpdesk Address: The email address and display name that represent your helpdesk (e.g. support@yourcompany.com). Used as the From address when relay modes are active.
  • System Address: Horizon's own mail infrastructure sends the email. Reliable and zero-config, but the From address won't be yours.
  • SMTP Relay: Your own mail server handles delivery. Required for relay-based delivery modes. Configured separately under Mail → SMTP Relay.
  • Internal Emails: Emails sent to people on your own team (e.g. digest notifications, internal alerts).
  • External Emails: Emails sent to contacts and end users (e.g. booking invites, ticket replies).

How It Works

There are three settings on this screen:

Your Helpdesk Address

Sets the display name and email address used when a relay delivery mode is active. If you're using System address modes only, this is informational.

Internal Emails — Delivery Mode

Controls how emails to your own team are sent:

  • System address — Sent from Horizon's mail system. No relay required.
  • Your helpdesk address — Sent through your SMTP relay, appearing to come from your helpdesk email. Requires an active relay.

External Emails — Delivery Mode

Controls how emails to contacts and end users are sent:

  • System address (reply-to: your helpdesk address) — Sent from Horizon's mail system, but with a Reply-To header pointing to your helpdesk address. Replies from recipients land in your helpdesk inbox. No relay required. This is the default.
  • Your helpdesk address — Sent through your SMTP relay, appearing to come from your helpdesk email. Requires an active relay.
  • Agent's address — Sent through your SMTP relay, appearing to come from the individual agent who triggered the email. Requires an active relay.

Common Use Cases

  • Getting started quickly: Leave both modes on their defaults (System address / System address with reply-to). No relay needed — emails just work.
  • Improving deliverability: Set up an SMTP relay and switch external emails to "Your helpdesk address" so emails arrive from your own domain.
  • Calendar invites and booking emails: Use relay mode so invites appear from your domain, which is required for proper calendar handling in some clients.
  • Per-agent personalization: Use "Agent's address" so contacts see a real person's name and email rather than a generic helpdesk address.

Related Articles

    • Related Articles

    • Registering Helpdesk Callbacks in Horizon

      Overview This article explains how to enable real-time ticket update notifications between your helpdesk and Horizon. Where to find it: Settings > Helpdesk > Callback Status Prerequisites Your helpdesk integration is connected and active in Horizon ...

    • How to Set Up SMTP Relay

      Overview Configure an SMTP Relay so that Horizon sends emails directly through your own mail server, improving deliverability and ensuring emails arrive as your address — not ours. This is especially important for calendar invites and other ...

    • Connecting Autotask to Horizon

      Overview This article walks you through creating an Autotask API user with webhook access and entering its credentials in the Horizon onboarding wizard. Prerequisites Administrator access to your Autotask account The Horizon onboarding wizard open ...

    • Adding Horizon Autotask Widgets

      Overview This article walks you through registering and configuring the Horizon widgets in Autotask, including the Ticket Insight panel and the full-screen Dashboard Widget. Prerequisites An active Autotask helpdesk integration configured in Horizon ...

    • Connecting Zoho Desk to Horizon

      Overview This article walks you through creating a Zoho Desk OAuth application and entering its credentials in the Horizon onboarding wizard. Prerequisites Administrator access to your Zoho Desk account The Horizon onboarding wizard open and on the ...