more thanks to you I really appreciated for your kindness, ill check all the question in my server .
Hi Sidurz, in order to answer your question we’re going to need a little more information from you.
-Do you have SMTP rules setup in your firewall? no i don’t have
-Do you have any specific SMTP restrictions specified on your Exchange server?
-Have you configured the MX records for your domain name properly?
-If you enable SMTP logging on the Exchange server, what kind of information do you see in the SMTP logs?
-Also check the event viewer and see if you can see any errors in there.
-How is your internal network setup in regards to physical wiring and VLANS, has that all been done correctly?
-Are you using anti-spam software or a third party anti-spam service? If so, have you configured it correctly to allow mail to flow through to your mail server?
A valuable resource I can point you to for Exchange help would be here.
Hope this helps!