error 550 smtp

Original issue background:A few days ago, ops colleagues suddenly found that Zabbix monitoring no longer send mail, and Zabbix monitoring interface status can be displayed. Because there have been similar problems, estimated to be 163 mailbox

1. Introduction The goal of Simple Mail Transfer Protocol (SMTP) is to transmit mail reliably and efficiently, which is independent of the transfer protocol.The delivery subsystem only requires a channel that can ensure the sequence of transmitted

From: Author: (2001-11-2307: 08: 00) 1. the goal of the Simple Mail Transfer Protocol (SMTP) is to deliver mail reliably and efficiently. it is independent of the transfer subsystem and requires only one channel that can ensure the order of

From: Author: (2001-11-2307: 08: 00) 1. the goal of the Simple Mail Transfer Protocol (SMTP) is to deliver mail reliably and efficiently. it is independent of the transfer subsystem and requires only one channel that can ensure the order of

Simple Mail Transfer Protocol (SMTP) 1.Introduction The goal of Simple Mail Transfer Protocol (SMTP) is to deliver mail reliably and efficiently. It is independent of the transfer subsystem and requires only one channel that can ensure the order of

Simple Mail Transfer Protocol (SMTP) 1. introduce The goal of Simple Mail Transfer Protocol (SMTP) is to deliver mail reliably and efficiently, independent of the transport subsystem and requiring only one channel that guarantees the order in which

Keyword: VC ++ SMTP protocol Email Delivery analysis this article introduces a method to implement Email Delivery in a program using SMTP protocol specifications and using SMTP protocol commands directly. Some key implementation code is provided in

Recently in the mail to send the interface to the problems encountered and solutions to tell you want to know the message to help people The original program part of the code is as follows Set mail message sender address, recipient address,

 Table (1) SMTP CodeCode definition421 service not available, hosts in the closing transmission channel brackets cannot provide normal services, close the transmission pipeline, and emails will be stuck on the host450 requested mail action not taken:

mail server server documentation domain login command Directory (?) [+] SMTP Protocol Analysis     1th Chapter.  SMTP Overview 1.1. The location of SMTP in mail communication SMTP, the Simple Mail delivery protocol, corresponds to the RFC document