I've been having this problem for 2 weeks and after clearing the queue, it worked for a while but the problem returns. What can I do to solve this problem? There's no problem sending email to localhost clients, only to some valid external email addresses.
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I've been having this problem for 2 weeks and after clearing the queue, it worked for a while but the problem returns. What can I do to solve this problem? There's no problem sending email to localhost clients, only to some valid external email addresses.