Your Message with subject Re: 1ST REVISED LINE PLAN KT11451 - HOBBS AW16 was not delivered to some recipients
The following recipient(s) could not be reached
jinlifazhou***@tom.com
Failure reason is as below:
Error Type: SMTP
   Remote server (202.108.255.210) issued an error.
   MailServer sent: 
   Remote server replied: 421 /0 connection limit exceeded

退信原因：连接超出了对方的限制，被临时禁止入站

解决方案：TOM.COM/163.NET对于入站的连接，做了一定的限制，比如每小时的连接，每天的连接等等，如果超过了范围，就会被临时拦截禁止入站。对于这类的错误，一般没多大的问题，稍后重新发送就可以发过去了，421是属于临时性的错误，而不是黑名单拦截类型的。