Slow to receive emails? – Disable Postfix Greylisting
Once you install iRedMail on your own VPS you might encounter issues by mails not being received on time or not being received at all. In my case I just had to disable the Postfix Policyd greylisting. I have seen many reject error messages in /var/www/mail.log : Jun 11 18:13:55 ProcessingEngine postfix/smtpd[13562]: connect from gateway01.websitewelcome.com[69.41.242.19] [...]