My mail server stopped sending or receiving emails after a reboot. I hope someone can help me.
running 6.0
Task 'mail.domain.com - Sending' reported error (0x800CCC6A) : 'Your outgoing (SMTP) e-mail server has reported an internal error. If you continue to receive this message, contact your server administrator or Internet service provider (ISP). The server responded: 451 Message refused by mail server.'
I also cannot receive emails.
Any help is greatly appreciated.
Henry