📧 SMTP Setup Guide

Email Signatures in <span class="grad">Thunderbird</span>

Set Badex as the outgoing SMTP server in Thunderbird. Professional DKIM-signed signatures on every email — Windows, Mac and Linux.

📡 Badex SMTP Connection Settings
Outgoing Server
smtp.signature.badex.app
Port
587
Security
STARTTLS
Authentication
Normal password
Username
your-email@yourdomain.com
Password
your Badex SMTP password
✅
Before you start — make sure you have:
  • ✓ A Badex Signature account (start free trial)
  • ✓ Your email domain added in Badex dashboard → Domains
  • ✓ An SMTP account created in Badex dashboard → SMTP Accounts
  • ✓ DNS records configured (SPF, DKIM, DMARC)

Overview

Mozilla Thunderbird is one of the most popular desktop email clients. By setting Badex as your outgoing SMTP server, every email you send gets a professional signature injected automatically — no Thunderbird add-ons or extensions needed.

Step-by-Step Setup

Step 1 — Open Account Settings

In Thunderbird, click ☰ Menu → Account Settings. Or right-click your email account in the left sidebar → Settings.

Step 2 — Go to Outgoing Server (SMTP)

In the left sidebar of Account Settings, scroll to the bottom and click Outgoing Server (SMTP).

Step 3 — Add New SMTP Server

Click Add to add a new outgoing server. Fill in:

Description: Badex Signature
Server Name: smtp.signature.badex.app
Port: 587
Connection Security: STARTTLS
Authentication Method: Normal password
User Name: your-email@yourdomain.com

Click OK.

Step 4 — Set as Default for Your Account

In Account Settings, click on your email account (e.g., your-email@yourdomain.com) in the left sidebar. Under Outgoing Server (SMTP), select Badex Signature from the dropdown.

Step 5 — Enter Password

When you send the first email, Thunderbird will ask for your SMTP password. Enter your Badex SMTP password (not your email password). Check Use Password Manager to remember this password.

Step 6 — Send Test Email

Compose a new email and send to Gmail. Check that the signature appears and headers show DKIM PASS.

🎉 Done!

Every email from Thunderbird now has your professional signature injected automatically. Works on Windows, Mac and Linux.

Troubleshooting

❓ Authentication failed error
Make sure the username is your full email address (e.g. john@company.com) and the password is your Badex SMTP password — not your email account password.
❓ Could not connect to SMTP server
Check your firewall or antivirus is not blocking port 587. Try temporarily disabling it to test.
❓ Signature appears twice
Disable Thunderbird's built-in signature (Account Settings → Signature text → clear it). Let Badex handle signatures server-side.
❓ SSL certificate error
Make sure Connection Security is set to STARTTLS (not SSL/TLS). Port must be 587.
Other Platform Guides
🟠cPanel / WHM 🔵Plesk 🔷Roundcube 🟢DirectAdmin 🦊Thunderbird 📘Outlook 🍎Apple Mail

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