How to Set Up Email Signatures in Roundcube — Badex Signature

Overview

Roundcube is the most popular open-source webmail client, used by millions of businesses on cPanel, Plesk, DirectAdmin and self-hosted mail servers. Badex Signature integrates with Roundcube by replacing the outgoing SMTP server — signatures are injected automatically on every email you send.

Method 1 — Configure per User in Roundcube

Step 1 — Open Roundcube Settings

Log into your Roundcube webmail. Click the ⚙ Settings icon in the top-right corner.

Step 2 — Go to Preferences → Server Settings

In Settings, click Preferences → then look for Server Settings or SMTP Settings. In newer Roundcube versions this may be under Sending Messages.

Step 3 — Enter Badex SMTP Details

SMTP Server: smtp.signature.badex.app
SMTP Port: 587
SMTP Encryption: STARTTLS
SMTP Username: your-email@yourdomain.com
SMTP Password: your Badex SMTP password

Step 4 — Save and Send Test Email

Click Save. Compose a new email and send it to your Gmail or Outlook. Your signature should appear automatically at the bottom.

Method 2 — Configure Server-wide (Admin)

If you manage the Roundcube server, you can configure Badex for all users in config/config.inc.php:

// Badex Signature SMTP Relay
$config['smtp_server'] = 'tls://smtp.signature.badex.app';
$config['smtp_port'] = 587;
$config['smtp_user'] = '%u'; // uses the logged-in user's email
$config['smtp_pass'] = '%p'; // uses the logged-in user's password

// Enable SMTP authentication
$config['smtp_auth_type'] = 'LOGIN';

⚠ Note: With %u and %p, Roundcube uses the user's login credentials. Each user needs a matching Badex SMTP account with the same email and password.

Verify It's Working

Send a test email to Gmail → ⋮ → Show original and check for:

X-BADEX-Signature-Processed: 1
DKIM: PASS

🎉 Done!

Every email from Roundcube now gets your professional signature automatically. No browser extensions, no plugins.

Troubleshooting

❓ SMTP Error: Authentication failed

Double-check your Badex SMTP username and password. The username must be the full email address.

❓ Connection refused on port 587

Your hosting may block outbound SMTP. Ask your provider to open port 587, or try configuring at the server level via cPanel/Plesk.

❓ Signature shows as plain text

Make sure your email is sent as HTML. In Roundcube Settings → Preferences → Composing Messages → set "Compose HTML messages".

❓ Cannot find SMTP Settings in Roundcube

Some cPanel hosts disable user SMTP settings. Use Method 2 (server config) or configure via cPanel mail relay instead.

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