> For the complete documentation index, see [llms.txt](https://docs.yeymail.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.yeymail.com/using-yeymail/sending-and-replying/thunderbird.md).

# Thunderbird

Thunderbird handles this well: you add the alias as an *identity* on the account you already read, with its own outgoing server.

## Before you start

In YeyMail: **Aliases → open the alias → Send as this alias (SMTP)** and set a password.

## 1. Add the outgoing server

1. **Account Settings** (hamburger menu → *Account Settings*).
2. Scroll to the bottom of the left column and click **Outgoing Server (SMTP)**.
3. Click **Add** and fill it in:

   | Field                 | Value                                      |
   | --------------------- | ------------------------------------------ |
   | Description           | e.g. "YeyMail shop alias"                  |
   | Server Name           | `mx1.yeymail.com`                          |
   | Port                  | `587`                                      |
   | Connection security   | **STARTTLS**                               |
   | Authentication method | Normal password                            |
   | User Name             | the full alias, e.g. `shop@yourdomain.com` |
4. Click **OK**.

## 2. Add the identity

1. Still in Account Settings, select your account at the top of the left column.
2. Click **Manage Identities…** → **Add…**
3. Set **Your Name** to whatever recipients should see, and **Email Address** to the full alias.
4. At the bottom, set **Outgoing Server (SMTP)** to the server you just created.
5. Click **OK**.

When you compose, the **From** dropdown now lists the alias. Thunderbird will prompt for the password the first time and offer to remember it.

## Replying automatically from the right alias

Thunderbird matches an incoming message's recipient against your identities, so a reply to mail that arrived on `shop@yourdomain.com` goes out from that identity by itself, provided the alias is listed as an identity, which the steps above did.

## If it doesn't work

**"Unable to connect"**: confirm *Connection security* is **STARTTLS** and the port is `587`. Choosing **SSL/TLS** switches Thunderbird to port 465, which we don't run.

**"Sending of the message failed" / relay denied**: the identity's email address must match the *User Name* on its outgoing server. Each alias needs its own identity and its own SMTP entry.


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