When Exchange 2007 is run under Windows Server 2008, clients who use Exchange 2007 may be repeatedly prompted for their credentials in Outlook Anywher

When Exchange 2007 is run under Windows Server 2008, clients who use Exchange 2007 may be repeatedly prompted for their credentials during Outlook Anywhere sessions. This issue occurs when NTLM Authentication is selected as the authentication method in the Exchange Proxy Settings dialog box for the Outlook profile on the client computer. This issue does not occur if Basic Authentication is selected as the authentication method in the Exchange Proxy Settings dialog box. By default, Kernel Mode Authentication is enabled in Internet Information Services (IIS) 7.0 on the Client Access server. To resolve this issue, disable Kernel Mode Authentication for Client Access servers that are running Windows Server 2008.


To disable Kernel Mode Authentication for Client Access servers that are running Windows Server 2008

At a command prompt, type the following command, and then press ENTER:


%systemroot%\system32\inetsrv\AppCmd.exe set config /section:system.webServer/security/authentication/windowsAuthentication /useKernelMode:false

Regards
Saad