SMTP errors can arise from various issues: mismatched sender and username, oversized messages, blacklisted receivers, or temporary server limits. To resolve, ensure your From address matches your login, reduce message size, and consider pausing campaigns. For Amazon SES, verify all email addresses used in your mailings.
If you encounter an SMTP connection error, it’s likely due to your email service provider rejecting one of your email addresses. Ensure your “from,” “reply-to,” and “bounce” addresses match the authenticated SMTP email. Check DNS functionality and connectivity using commands like `dig` and `telnet`. If issues persist, contact your ISP for support.
Campaigns may pause or fail to send emails due to SMTP authentication errors, incorrect credentials, or blocked ports. Ensure you’re using the correct email for authentication, check your sending limits, and consider changing your delivery method. If issues persist, pause and resume your campaign later.
To enhance Mailster’s email delivery rates, consider reducing the cron interval, increasing the number of emails sent at once, or selecting a different delivery method. Remember, delivery speed averages 1-2 emails per second, and server capacity and connection quality can impact performance.
If your email campaign isn’t sending, check key settings: verify newsletter delivery and cron job functionality, ensure server resources are adequate, and confirm you’ve selected recipients. Additionally, review any potential server issues or conflicts with third-party plugins. For assistance, contact your provider if you hit sending limits.
Mailster sends emails in batches to avoid server timeouts and delivery bans. You can enable automatic batch size adjustment based on your server’s capabilities. However, be cautious of your email provider’s limits, as this option prevents manual size settings and may require time to optimize batch delivery.
When starting with email marketing or changing providers, avoid sending too many emails at once. Use Mailster’s Warmup settings to gradually increase your email throughput. Set a timeframe for warming up your server, allowing Mailster to adjust send rates and batch sizes over time for optimal delivery.
Optimize your email marketing by balancing throughput rate and batch size to avoid server timeouts. Determine your server’s email capacity and adjust your cron interval for efficient sending. For instance, sending 20 emails every 5 minutes allows for 240 emails per hour, while 40 doubles that to 480.
If you experience issues sending your campaigns, verify your cron setup, as it’s crucial for successful delivery. Check for cron locks that may prevent duplicate emails and ensure your RSS feed URLs are accessible. For further assistance, consult our help article.
SMTP (Simple Mail Transfer Protocol) utilizes various ports (25, 993, 465, 587) for email sending, but providers may block specific ports or restrict use to their own servers. To check port accessibility, visit Settings => Newsletter => System Info. Consider alternative delivery methods or free plugins if ports are blocked.
Mailster allows you to enhance email delivery by overriding the default wp_mail function. Choose from three settings: bypass Mailster, use it for all emails, or apply a template. Additionally, control how Mailster interacts with third-party content types, ensuring compatibility and effective email delivery.
Mailster offers two default delivery methods: Simple SMTP and SMTP. Simple SMTP is not recommended for bulk mailing due to provider limits. For larger subscriber lists, use SMTP and check with your host for credentials. Additional methods like AmazonSES, SparkPost, Mailgun, SendGrid, and Gmail can be added via plugins.
Sendmail is a widely used mail transfer client, but ensure the path “/usr/sbin/sendmail” is correct and you have permission to use it, as shared hosts may disable this feature. For bulk mailings, consider using a dedicated email provider or a free WordPress plugin to avoid limits and errors.
Your provider restricts bulk and outgoing mail. Consider using dedicated email services like SendGrid, Mandrill, Amazon SES, or SparkPost. If Mailster lacks a specific add-on, you can revert to SMTP. Explore free WordPress plugins for various delivery methods.