Lately my registrations went down. As I wondered what the problem could be I test registered an account and I discovered that my vBulletin forum is not sending any mails out!

So I sent an email via Diagnostics and it came threw without any spam problems.

Doe anyone know how to solve this problem?

Thanks in advance.

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I think I solved the problem.

I recently made a test environment using this useful How-To (LINK).

But I accidently forgot to remove [ define('DISABLE_MAIL', 1); ] from config.php.