Email setup

Keep your mailbox

You don't have to move support@acme.com. With an adapter that receives on its own domain (Resend), keep the mailbox where it is and copy its mail to a receiving subdomain:

1. Add a receiving subdomain

   For example in.acme.com, with its MX record pointing at your provider. The apex domain's MX stays on Microsoft 365 or Google Workspace.

2. Copy support@ to it

   In Exchange, a mail flow rule: when the recipient (or, for a group, the To or Cc box) is support@acme.com, Bcc support@in.acme.com. In Google Workspace, a routing rule that adds a recipient. Your mailbox keeps its copy.

3. Use the subdomain as replyAddress

   Replies go out from support@acme.com with a reply address on the subdomain, so answers come straight back to the ticket.

Prefer one place for everything? The Microsoft 365 and Gmail adapters read and send from the mailbox itself, and record replies your team sends from Outlook or Gmail on the ticket.

Threading

A message joins an existing ticket when, in this order:

• it was sent to the ticket's reply address, support+t-<token>@in.acme.com, which survives mail clients that drop headers;
• its In-Reply-To or References headers name a message on the ticket;
• the provider says it belongs to the same thread (Gmail, Microsoft 365);
• for SMS, WhatsApp and Telegram, it comes from the same person on the same channel.

A reply to a solved ticket reopens it within reopenWindowDays (14 by default); after that it opens a new ticket that links back.

What the ticket shows

Only what the person wrote this time. Quoted history is cut at reply headers in English, French and Arabic, and at Outlook's From/Sent blocks. Signatures are removed when the mail client marks them (Outlook, Outlook mobile, Gmail, Thunderbird), and the "Sent from my iPhone" lines are dropped. The full message stays one click away, and HTML email renders sanitized in a sandboxed frame with remote images off until an agent allows them.

Automatic mail

Out-of-office replies, bounces, mailing lists and other automated mail (detected from Auto-Submitted, Precedence, list headers, null return paths and delivery reports) are recorded on the ticket but never reopen it, notify anyone or get an acknowledgement. Mail from your own addresses and from ignoreFrom is dropped, so a copy rule can't loop.

Sender authentication

Deliverability

Replies are sent from your domain, so it needs SPF, DKIM and a DMARC record for every service that sends as it (your mailbox provider and your sending provider). Acknowledgements carry Auto-Submitted: auto-replied so other auto-responders don't answer them.