SMTP Error 451

 when i try to send mail through server i get the message SMTP Error 451 which indicates the user exceeds the limits set on the email server for sending emails.  the question from where i can change this sitting in CWP7pro panel

N.B : actually I can't totally send or receive mail on the server

 

You can set message throughput limits under the Packages > Packages menu item (don't you love the redundancy there?).
It is set under the Hourly Emails setting.

You can set message throughput limits under the Packages > Packages menu item (don't you love the redundancy there?).
It is set under the Hourly Emails setting.

Many thanks for your reply , but unfortunately not solve the problem and still get the same message , is there any other location or place for where i can edit mail setting or activate mail if it was disable by mistake

pleas if any one can help me in this problem ,  my web site installed on CWP7pro panel and web site can't receive or send any mail through the server , So what sitting i need to check to solve this problem

also when try to send mail through mail account on server i get the following error 
" SMTp Error(451) failed to add recipient "***@***" (4.3.0<****@****> temporary lookup failure "

Postfix has its own mail size delivery and quota settings. Dovecot does also. Welcome to the rabbit hole! This gets deep, FAST.