Outlook 2007 unable to connect to Exchange server 2003 when I updated the Windows Server 2003 with SP2. Before the update to the OS of Exchange Server 2003 it works very fine. Any help.

Hi, Can you logon the mailbox in OWA on the Exchange server? Please Ping the server to make sure network is working fine. Also verify the application event log in client computer and server computer to see if there is any error when the connection failed. If there is any error message pop up when you try to connect, please copy and paste it. Tahnks. Fiona Liao TechNet Community Support

Thank you for your reply. There is no problem in OWA i tried it there is no problem also with POP3 protocol I enable it but without the calendar. But there is possible complication of the setup that I have. Servers: (1) Windows Server 2008 R2 Standard ed. 64-bit Rules: AD, Certificate Services, DNS Server, Hyper-V Hyper V - 1 [Windows Server 2003 Standard w/ sp2 32bit Installed Exchange Server 2003 w/ sp2 (newly installed)] (2) Windows Server 2008 R2 Standard ed. 64bit Installed: Lync Server 2010 Standard Ed. (3) Windows Server 2003 Standard Ed 32bit w/ sp2 child domain Client with Office Outlook 2007 with patch for Lync Server 2010 (presence) installed Before the installation of the service pack 2 to of the OS of the Exchange Server the Outlook 2007 has no problem connecting to Exchange server.

Solved the problem in Outlook 2007 and Outlook 2010 connecting to Exchange Server 2003 In creating account on Server Settings. Go to More Settings on General Tab (5 tabs in Outlook 2007 and 4 tabs in Outlook 2010) be sure "Manually Control Connection State" is selected Then in Security Tab Uncheck "Encrypt data between Microsoft Outlook and Microsoft Exchange" It will be OK even in my setup with Lync Server.