I fix the problem after i visited exchange.org website and i follow the instruction that have been given
How do the mail rejection is happen from the server (postmaster) or from client - outlook?
i dont't know because i don't see failure message in my outlook, the message that i saw was :
"This is an automatically generated Delivery Status Notification. Your message has been successfully relayed to the following recipients, but the requested delivery status notifications may not be generated by the destination milis78spuw46@xxxxxxxxx"
but when i go into yahoo mail (milis78spuw46@xxxxxxxxx), i don't see my message there?
is my server still blocked by all mail server in the world?