Reply from your domain

mxproxy delivers the email sent to hello@yourcompany.com to the inbox you already use. To reply as hello@yourcompany.com instead of your personal address, your email app sends through our SMTP server, which signs the message with your domain’s DKIM key.

1. Create the SMTP credential

1. In the dashboard (app.mxproxy.dev), open the domain. It must be verified, with SPF and DKIM ok: otherwise the recipient’s Gmail or Outlook will distrust the message.
2. Under SMTP credentials, pick the user name (for example hello) and create the credential.
3. Copy the password right away: it is shown only once. If you lose it, revoke the credential and create another.

The settings you will use in any app:

A credential only sends as addresses of its own domain: with the credential of yourcompany.com you can send as hello@, sales@ or any other address of yourcompany.com.

2. Gmail

1. In Gmail on a computer, click the gear → See all settings → the Accounts and Import tab.
2. Under Send mail as, click Add another email address.
3. Enter the name recipients will see and the address (hello@yourcompany.com). Keep Treat as an alias checked if the inbox is yours. Click Next Step.
4. SMTP Server smtp.mxproxy.dev, port 587, the credential’s user name and password, and Secured connection using TLS. Click Add Account.
5. Gmail sends a confirmation code to hello@yourcompany.com. Since mxproxy forwards that address to your Gmail, it arrives within seconds: click the link or paste the code.
6. Optional: under When replying to a message, choose Reply from the same address the message was sent to. A reply to an email sent to hello@ then goes out as hello@ without you picking it.

To write a new email as your domain, pick the address in the From field. On the mobile app, the address shows up in From once it is set up on a computer.

3. Outlook

Outlook on the web (Outlook.com) and the new Outlook do not offer a separate outgoing server for an address outside Microsoft. Use classic Outlook for Windows, which can receive through one account and send through another server:

1. File → Add Account. Type hello@yourcompany.com, open Advanced options, check Let me set up my account manually and choose IMAP.
2. Incoming: the IMAP server of the inbox mxproxy forwards to (for example outlook.office365.com port 993 SSL/TLS for Outlook.com, or imap.gmail.com port 993 for Gmail), with that inbox’s login.
3. Outgoing: server smtp.mxproxy.dev, port 587, encryption STARTTLS.
4. In More Settings (or Account Settings → Change → More Settings) → Outgoing Server tab: check My outgoing server (SMTP) requires authentication → Log on using, with the mxproxy credential’s user name and password.
5. Send a test email to an outside address and check the sender.

4. Other apps

Thunderbird, Apple Mail, the iPhone and Android mail apps, and systems that send email (WordPress, ERPs, printers) use the same settings as the table above: create an identity or an outgoing server with smtp.mxproxy.dev:587, STARTTLS and the credential. Give each system a credential of its own: you can revoke it without touching the others.

5. If it does not work

• Authentication failed: the user name is the credential’s full address and the password is mxproxy’s. The credential may have been revoked: create another.
• “Sender not allowed” (553): the address in From is not of the credential’s domain.
• Cannot connect: use port 587 with STARTTLS (not implicit SSL) and check that your network does not block the port.
• Sending refused late in the day: the plan reached its daily message limit (forwarded and sent mail count together). See Usage and plan in the dashboard.
• Lands in the recipient’s spam: check in the dashboard that the domain’s SPF and DKIM are ok.

Still stuck? Write to contato@mxproxy.dev.