Mailster Knowledge Base
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Gettings Started
Start your journey with Mailster by learning the essentials for setting up and running your first email campaigns.
Account & License
Learn how to manage your Mailster account and licenses, updating account details, and troubleshooting common licensing issues.
Troubleshoot
Find solutions to common problems and technical issues you might encounter while using Mailster.
Integration
Explore how Mailster connects with sending providers, third-party plugins, and other tools to extend its functionality and improve your email delivery.
Automation
Explore how Mailster connects with sending providers, third-party plugins, and other tools to extend its functionality and improve your email delivery.
WooCommerce
Explore how Mailster connects with sending providers, third-party plugins, and other tools to extend its functionality and improve your email delivery.
Popular Articles
SMTP Error: data not accepted
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.…
SMTP Error: Could not connect to SMTP host.
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…
How do I know if my cron is working correctly?
Mailster requires a cron job to send campaigns. Check its status under Newsletter > Settings > Cron, where you can see the last trigger time and details. If the cron hasn’t run recently, verify your…
Access to admin-ajax.php is blocked
The admin-ajax.php file is crucial for Mailster’s backend functions. If it’s blocked, issues may arise from plugin conflicts, host firewalls, .htaccess rules, or cross-domain mismatches. To resolve Ajax problems, check and adjust these elements or…
What is a Cron Lock?
Mailster prevents duplicate emails by creating a cron lock during campaign processing. If a lock is active, you’ll see a notification when accessing the cron URL. Locks are released automatically after processing, but may require…
How can I add a captcha to the sign up form?
Discover two free plugins for enhanced form security: Mailster Cool Captcha and Mailster reCaptcha™. Both are available on the WordPress Plugin repository, ensuring your forms are protected from spam.
Creating a series in Mailster
This article recommends using Automation for creating engaging newsletter series in Mailster, known as drip campaigns. It outlines steps to set up a series, starting with a Welcome Campaign, followed by subsequent campaigns triggered by…
Mailster and WooCommerce
Enhance your WooCommerce shop with a free WordPress add-on to convert customers into newsletter subscribers. Automate email workflows based on product purchases, customize subscriber lists, and manage signup options. Ensure compliance with legal requirements by…
Working with action hook auto responders
In this fourth part of our Mailster autoresponder series, we explore Action Hook Auto Responders. These advanced tools require WordPress coding knowledge and are triggered by specific actions. Learn to customize campaigns, define delivery options,…
SMTP Error: Could not authenticate
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…