请问这个是什么意思?

goyeah

ERROR: One or more of your mailservers does not accept mail from "<>". Mailservers are required by RFC1123 5.2.9 to accept mail from "<>". By refusing this mail, you will never get reject/bounce messages, or return receipts, and you may get other mail server admins upset at you if they have to deal with your bounce messages.<br>
ERROR: mail.tms-cn.com's MAILFROM <> response: 501 input error. .