Q. Catchall Account Is Not Enabled? Why Is this so?
A. Catchall Account is spammers paradise. It also defeats few checks which other servers (remote servers) may be implementing to check spam. Things like sender verification if implemented on any remote server would always pass. This would mean that any SPAMMER could just send out spam forging headers as *@yourdomain.tld and when a recepient on the remote server does not exist, the message would bounce back to *@yourdomain.tld. Since you have catchall enabled all such bounce messages would fill up your disk space.
