vBulletin 3 is end of life and will not be receiving future development. Warning: vBulletin 3.8.11 is not compatible with PHP 7.2.0 or higher.
Welcome to the vBulletin support forums! In our community forums you can receive professional support and assistance with any issues you might have with your vBulletin Products.
vB uses the server for it's email. Assuming you have not disabled emails in the Admin CP or in config.php, then if there are problems the issue is either with the server itself or on the receiving end.
Please see this page for help troubleshooting email problems:
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