I did not find Ms. Exchange server forum in this site, sorry If I posted this message at the wrong place.. but this is my top urgent problem and hopefully there are someone can help me to solve my problem, my problem is I can send mail thru my Ms. Exchange server (Ms. Exchange 5.5) to internal and external, but I can not retrieve mail from external only.. is there any idea or suggestion?
Thanks in advance

Best regards
Winan