Connecting Custom SMTP

BuffSend allows you to connect virtually any email sending service or private mail server that supports the Simple Mail Transfer Protocol (SMTP). This is ideal for using high-volume transactional email services like SendGrid, Mailgun, AWS SES, Mailjet, Postmark, or your own configured mail server.

Information You Will Need

Before you start, you need to obtain the correct SMTP credentials from your email provider or server administrator. You will typically need:

  • SMTP Server Address (Host): The address of the mail server (e.g., smtp.sendgrid.net, email-smtp.us-east-1.amazonaws.com, mail.yourdomain.com).
  • SMTP Port: The communication port number. Common ports are:
    • 587 (Recommended for TLS encryption)
    • 465 (Used for SSL encryption)
    • 2525 (Often used as an alternative to 587)
    • 25 (Standard SMTP, often unencrypted - use with caution)
  • SMTP Username: Your login username for the SMTP server. This might be your full email address, an API key username (common for services like SendGrid), or a specific system username.
  • SMTP Password: The password associated with your SMTP username. This could be your email account password, an App Password (if required by your provider for less secure apps), or an API key (common for transactional services). Treat API keys like passwords!
  • Encryption Method: Specify whether the connection should use TLS (sometimes called STARTTLS), SSL, or None. TLS (usually on port 587) is the most common and recommended secure method. SSL (usually on port 465) is also secure. Avoid "None" unless absolutely necessary and you understand the security implications.

Where to find this information? Check the documentation or account settings of your specific email provider (SendGrid, Mailgun, AWS SES, your hosting provider, etc.). Search for "SMTP settings" or "SMTP credentials".

Steps to Connect in BuffSend:

  1. Navigate to the Senders section in BuffSend.
  2. Click "Add Sender" or "Connect New Sender".
  3. Select the "Custom SMTP" or "Other / SMTP" option.
  4. Carefully enter the SMTP Server Address, Port, Username, and Password you gathered.
  5. Select the correct Encryption Method (TLS, SSL, or None) based on the port and your provider's requirements.
  6. Enter the "From Email" address this sender will use (e.g., you@yourdomain.com). This should typically match the domain you authenticated with your SMTP provider.
  7. Optionally, enter a "From Name" (e.g., "Your Name" or "Company Name").
  8. Click "Verify Connection" or "Save Sender". BuffSend will attempt to connect to the SMTP server using the provided credentials.
  9. If the connection is successful, the sender will be added to your list and marked as verified.

Important Considerations:

  • Authentication: Ensure your sending domain is properly authenticated with your SMTP provider using SPF and DKIM records at minimum. Many providers require this before allowing sending.
  • Sending Limits & Reputation: Be aware of any sending limits imposed by your SMTP provider. Your sender reputation is managed by your provider and depends on your sending practices.
  • Password Security: If using a regular email password, ensure it's strong. If using an API key, store it securely and consider rotating it periodically.

Troubleshooting:

  • Authentication Errors: Double-check your username and password/API key. Ensure the correct combination is used (e.g., API username with API key, not account password). Check if an App Password is required.
  • Connection Timeouts: Verify the SMTP Server Address and Port. Check if a firewall might be blocking the connection from BuffSend's servers to your mail server on the specified port.
  • Encryption Mismatches: Ensure the selected Encryption Method matches the Port number and what your server expects (e.g., TLS for 587, SSL for 465).
  • Consult the specific error message provided by BuffSend and cross-reference with your email provider's documentation.
  • See the general Sender Connection Issues guide.

← Back to Knowledge Base