Hi Users, I am using ispconfig since last 5-6 months for hosting couple of websites. Lets say example1.com & exampled2.com both hosted on same cloud server. I moved example2.com to IIS on my home server, I deleted example1.com domain, DNS, mailboxes from ispconfig panel. Now i am trying to send mail from example1.com to exmapled2.com. it shows below error SMTP Error (550): Failed to add recipient "[email protected]" (5.1.1 <[email protected]>: Recipient address rejected: User unknown in virtual mailbox table). I have commented below line in main.cf #smtpd_reject_unlisted_sender = no Still I am not able to send mails.