User - MX Filter is a free Joomla extension designed to protect your site from unwanted user registrations. It filters registration attempts based on the MX server of the user's email domain, preventing spam and problematic email hosts from cluttering your database. Built for Joomla users who value a clean, secure site, this extension ensures only legitimate users can register, providing peace of mind without impacting performance. Let’s keep your inbox clean and protect your user base—starting today!
User - MX Filter Features
- MX Record Validation: Prevent registration using email addresses from domains without a valid MX record.
- Blacklist Filtering: Block registrations from email addresses matching entries in a configurable blacklist. Partial domain matches are possible – for example, a blacklist entry of example.com will match any subdomain of example.com (e.g., mail.example.com).
- Post-Registration Protection: Prevent users from changing their email address to blacklisted MX hosts.
v5.0.2
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How User - MX Filter Works
- Spam Registrations: This plugin prevents fake or bad email domains from creating unnecessary accounts that cannot receive notifications or registration confirmation emails.
- Problematic Email Hosts: This plugin blocks registration from email hosts that are known to be unreliable, competitive, or otherwise undesirable. "Problematic" hosts can reject mail, be known spam sources, or be competitors.
Technical Details
The extension works by first checking that the domain has an MX record. Then it checks the domain against a blacklist. If the registration matches a blacklist entry, it is blocked. Partial domain matches are supported, allowing administrators to block entire domains and their subdomains with a single blacklist entry.
Built for Me - Given to You
As detailed in an article titled Microsoft Deliverability - SendGrid and Blacklists, I have issues sending email to Microsoft hosted domains. Though I've tried to purchase IP addresses to escape the MS blacklist, it seems like they have blacklisted every IP address except those assigned to themselves and Google (and probably the non-shared SendGrid IPs). In the article, you can see several examples of well known IT professionals lamenting the inescapable Microsoft blacklist. This plugin allows me to block based on MX rather than domain.
Are you ready to take control of user registrations and say goodbye to invalid or unreachable email addresses?