Sending & SMTP Settings
SMTP Configuration
SMTP configuration allows you to connect Rollout Email to an external mail server for sending campaigns. Each configuration stores the connection credentials and default sender details required for email delivery.
Accessing SMTP Configurations
Go to Mail Configs → SMTPS.
Click New SMTP or open an existing configuration.
Enter the required connection details.
Save the configuration.
SMTP Configuration Fields
The configuration form contains two main sections.
General Profile Information
Field | Description |
|---|---|
Configuration Name | A name used to identify the SMTP profile inside campaigns. |
Active Status | Enables or disables the SMTP configuration. |
Default From Name | The sender name displayed to recipients. |
Default From Email | The default email address used for sending. |
Server Gateway Credentials
Field | Description |
|---|---|
SMTP Host Address | The hostname of the SMTP server. |
SMTP Port | The port used to connect to the SMTP server. |
Transport Security Layer | The security method used for the SMTP connection. |
SMTP Username / Access Key | The username or access key provided by the email service. |
SMTP Password / Secret Token | The password or secret token used for authentication. |
Example SMTP Credentials
The following is an illustrative example only. Replace these values with the credentials provided by your SMTP service.
Setting | Example |
|---|---|
Configuration Name | Mailgun Free SMTP |
Active Status | Enabled |
Default From Name | Your Company |
Default From Email |
|
SMTP Host Address |
|
SMTP Port |
|
Transport Security Layer | TLS / STARTTLS |
SMTP Username / Access Key |
|
SMTP Password / Secret Token |
|
Do not use the example credentials above. Use the exact host, port, username, and password supplied by your email provider.
SMTP Ports
Different SMTP services support different ports and security methods. Use the port recommended by your provider.
Port | Common Use | Security |
|---|---|---|
25 | Server-to-server SMTP relay and some provider configurations. | Usually plain SMTP with optional STARTTLS. |
465 | Secure SMTP submission using an encrypted connection from the beginning. | Implicit TLS. |
587 | Standard email submission from an application or email client. | STARTTLS is commonly used. |
2525 | Alternative submission port when standard ports are blocked. | Usually STARTTLS, depending on the provider. |
Port 587 is the standard message-submission port. Port 465 is used for implicit TLS, while port 2525 is commonly offered as an alternative when network restrictions affect standard SMTP ports. Port 25 is primarily associated with SMTP relay between mail servers.
When to Use Each Port
Port 25
Use port 25 when:
Your provider specifically instructs you to use it.
You are configuring server-to-server mail relay.
Your mail server is authorized to send through the provider on this port.
Port 25 may be blocked or throttled by hosting providers and internet service providers. It is generally not the preferred choice for application-based email submission.
Port 465
Use port 465 when:
Your provider requires implicit TLS.
The SMTP service specifically documents port 465 for secure connections.
You want the connection to begin with encryption.
Select the TLS option required by your provider. Do not configure port 465 as STARTTLS unless the provider explicitly supports that combination.
Port 587
Use port 587 when:
Your provider recommends standard SMTP submission.
Your application supports STARTTLS.
You want a commonly supported port for authenticated email delivery.
Port 587 is generally the preferred starting point for application-based SMTP configuration when the provider does not specify another port.
Port 2525
Use port 2525 when:
Port 587 is blocked or unavailable.
Your provider offers port 2525 as an alternative.
You need an alternative SMTP submission port.
Port 2525 is not a standard SMTP port, but several email providers support it for the same general purpose as port 587.
Choosing the Correct Security Method
The SMTP port and security method must match the provider's requirements.
Security Method | Typical Port | Description |
|---|---|---|
TLS / STARTTLS | 587, 2525, sometimes 25 | The connection begins without encryption and is upgraded to TLS using STARTTLS. |
Implicit TLS | 465 | The connection is encrypted immediately. |
Plain / No TLS | Only when explicitly supported | The connection does not use TLS. Avoid this when secure authentication is available. |
For secure email submission, use the provider's recommended TLS configuration. STARTTLS on port 587 and implicit TLS on port 465 are both established secure submission methods when correctly configured.
Example: Mailgun SMTP Configuration
The following example shows how a Mailgun SMTP profile might be configured. The credentials must come from your own Mailgun account.
Field | Example |
|---|---|
Configuration Name | Mailgun Free SMTP |
SMTP Host Address |
|
SMTP Port |
|
Transport Security Layer | TLS / STARTTLS |
SMTP Username / Access Key | Your Mailgun SMTP username |
SMTP Password / Secret Token | Your Mailgun SMTP password |
Mailgun documents support for ports 25, 465, 587, and 2525. Its documentation specifies TLS for port 465 and STARTTLS-capable connections for ports 25, 587, and 2525.
Saving the Configuration
Enter the configuration details.
Confirm that the SMTP host and port are correct.
Confirm that the security method matches the selected port.
Enter the SMTP username and password or secret token.
Confirm the default sender name and email address.
Ensure Active Status is enabled if the profile should be available for campaigns.
Click Create or Save changes.
Editing an SMTP Configuration
Go to Mail Configs → SMTPS.
Open the SMTP configuration you want to update.
Modify the required fields.
Review the connection details.
Click Save changes.
Deleting an SMTP Configuration
Open Mail Configs → SMTPS.
Select the SMTP configuration.
Click Delete.
Confirm the deletion if prompted.
Review campaigns that use the SMTP profile before deleting or disabling it.
Troubleshooting SMTP Connections
Problem | Possible Cause | Recommended Action |
|---|---|---|
Connection refused | The port is blocked or unavailable. | Try the provider's recommended alternative port. |
Authentication failed | Username or password is incorrect. | Verify the SMTP credentials. |
TLS error | The security method does not match the port. | Check whether the provider requires STARTTLS or implicit TLS. |
Sender rejected | The sender address is not authorized. | Use a verified sender address or domain. |
Connection timeout | The host or port cannot be reached. | Verify the SMTP host, port, and firewall rules. |
Important Notes
Use credentials supplied by your SMTP provider.
Do not share SMTP passwords or secret tokens.
Keep the SMTP host, port, and security method consistent with the provider's documentation.
Use port 587 as the default starting point for SMTP submission unless your provider specifies another port.
Use port 2525 when the provider supports it and standard submission ports are unavailable.
Do not assume that every SMTP provider supports every port.
Verify the sender email address before sending campaigns.
SMTP Configuration Checklist
Configuration name entered
Active status selected
Default from name entered
Default from email entered
SMTP host address entered
Correct SMTP port selected
Correct security method selected
SMTP username entered
SMTP password or secret token entered
Sender address verified with the provider
Configuration saved
SMTP profile available for campaign selection