SMTP Configuration

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Overview

Runlayer uses SMTP to send transactional emails such as user invitations, password resets, and system notifications. You can configure custom SMTP settings to use your preferred email provider or service.

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Default Configuration

By default, Runlayer is configured to use Resend SMTP service:

• Host: smtp.resend.com
• Port: 587
• Username: resend
• Encryption: TLS

To use the default configuration, you only need to provide an API key as the password. Contact support if you’d like us to set up a Resend account for your organization.

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Supported SMTP Providers

Runlayer works with any SMTP-compatible email service. Here are configuration examples for popular providers:

Gmail / Google Workspace

Settings:

• Host: smtp.gmail.com
• Port: 587
• Username: Your Gmail address (e.g., [email protected])
• Password: App-specific password (not your regular Gmail password)
• Encryption: TLS

Setup Steps:

1. Enable 2-factor authentication on your Google account
2. Generate an App Password
3. Use the app password in the SMTP configuration

Never use your regular Gmail password. Always use app-specific passwords for better security.

Microsoft 365 / Outlook

Settings:

• Host: smtp-mail.outlook.com
• Port: 587
• Username: Your Microsoft 365 email address
• Password: Your account password or app password
• Encryption: TLS

Setup Steps:

1. Ensure SMTP AUTH is enabled for your organization
2. For enhanced security, use app passwords

Amazon SES

Settings:

• Host: Regional endpoint (e.g., email-smtp.us-east-1.amazonaws.com)
• Port: 587
• Username: Your SES SMTP username
• Password: Your SES SMTP password
• Encryption: TLS

Setup Steps:

1. Set up Amazon SES in your AWS account
2. Create SMTP credentials in the SES console
3. Verify your sending domain
4. Request production access if needed

SendGrid

Settings:

• Host: smtp.sendgrid.net
• Port: 587
• Username: apikey
• Password: Your SendGrid API key
• Encryption: TLS

Setup Steps:

1. Create a SendGrid account
2. Generate an API key with “Mail Send” permissions
3. Use apikey as the username and your API key as the password

Mailgun

Settings:

• Host: smtp.mailgun.org
• Port: 587
• Username: Your Mailgun SMTP username (usually starts with postmaster@)
• Password: Your Mailgun SMTP password
• Encryption: TLS

Setup Steps:

1. Create a Mailgun account
2. Add and verify your domain
3. Find your SMTP credentials in the domain settings

Postmark

Settings:

• Host: smtp.postmarkapp.com
• Port: 587
• Username: Your Postmark server token
• Password: Your Postmark server token
• Encryption: TLS

Setup Steps:

1. Create a Postmark account
2. Create a server for transactional emails
3. Use your server token as both username and password

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Configuration Steps

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Troubleshooting

Authentication Failed

Common causes:

• Incorrect username or password
• 2FA enabled without app password
• SMTP not enabled for the account

Solutions:

• Verify your credentials
• Generate an app-specific password
• Check your email provider’s SMTP settings

Connection Timeout

Common causes:

• Incorrect host or port
• Firewall blocking SMTP traffic
• Wrong encryption settings

Solutions:

• Verify the SMTP host and port
• Check firewall settings
• Try different encryption options (TLS vs SSL)

Emails Not Delivered

Common causes:

• Sender domain not verified
• Email marked as spam
• Rate limits exceeded

Solutions:

• Verify your sending domain with your email provider
• Check spam folders
• Review your email provider’s sending limits

SSL/TLS Certificate Errors

Common causes:

• Outdated certificates
• Self-signed certificates
• Certificate name mismatch

Solutions:

• Ensure your system’s certificate store is up to date
• Contact your email provider for certificate issues
• Try using a different encryption method

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Rate Limits and Quotas

Different email providers have various sending limits:

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Getting Help

If you encounter issues with SMTP configuration: