外域入信失敗原因
- ? 550 Connection frequency limited
- ? 550 Sender frequency limited
- ? 550 Domain frequency limited
- ? 550 Ip frequency limited
- ? 550 Mail content denied
- ? 550 Mailbox not found
- ? 552 Message too large
- ? 501 Bad address syntax
- ? 550 Mailbox unavailable or access denied
- ? 550 Mail is rejected by recipients.
- ? 550 Connection denied
- ? 550 Sender domain is a local domain.