Hello Mark Fugatt Here is the solutions for my problem, I already do it and is working fine. I will work in my security now. Thanks a lot Mark. Q. Before we go any further, I need your help to clarify the following information with you: Did you a) Configure your SBS server to retrieve emails from an Internet POP3 server through POP3 Connector; Or b) Configure a client computer to be able to check emails on SBS server through the POP3 service from the Internet; From your description, it seems that your case appears most likely is the second scenario, because clients can connect to their POP3 Mailboxes from LAN, not from the Internet. Please perform following steps: 1. By default, the Default POP3 Virtual Server is stopped, so you need to go to the Exchange Server Management\Servers\Yourserver\Protocols\POP3, right click the Default POP3 Virtual Server and select Start. Then rerun the CEICW: a) Expand to Server Management\Standard Management\To Do List\Connect to the Internet. b) After the Configure E-mail and Internet Connection Wizard starts, follow the instructions until you reach the Firewall page. c) Click Enable Firewall, and then click Next. d) Click Add. e) Type Microsoft Exchange POP3 in the Service name box, click TCP in the Protocol box, type 110 in the Port box, and then click OK. f) Finish rest of the wizard.