Hi All, Users are not able to access Active Sync and i see the below errors on the CAS server. Any help is highly appriciated. ===================================================== Log Name: Application Source: Microsoft-Windows-IIS-W3SVC-WP Date: 12/14/2010 1:51:56 PM Event ID: 2268 Task Category: None Level: Error Keywords: Classic User: N/A Computer: Abc.com Description: Could not load all ISAPI filters for site 'DEFAULT WEB SITE'. Therefore site startup aborted. Event Xml: < Log Name: Application Source: Microsoft-Windows-IIS-W3SVC-WP Date: 12/14/2010 1:51:56 PM Event ID: 2274 Task Category: None Level: Error Keywords: Classic User: N/A Computer: Xyz.com Description: ISAPI Filter 'D:\Program Files\Microsoft\Exchange Server\ClientAccess\owa\auth\owaauth.dll' could not be loaded due to a configuration problem. The current configuration only supports loading images built for a x86 processor architecture. The data field contains the error number. To learn more about this issue, including how to troubleshooting this kind of processor architecture mismatch error, see http://go.microsoft.com/fwlink/?LinkId=29349. =============================================================

ISAPI Filter 'D:\Program Files\Microsoft\Exchange Server\ClientAccess\owa\auth\owaauth.dll' could not be loaded due to a configuration problem. The current configuration only supports loading images built for a x86 processor architecture. The data field contains the error number. To learn more about this issue, including how to troubleshooting this kind of processor architecture mismatch error, see http://go.microsoft.com/fwlink/?LinkId=29349. ============================================================= I am assuming that you are running a 64-bit OS and the 64-bit version of Exchange 2007 (if not, 32-bit is not supported. I found this related thread: http://social.technet.microsoft.com/Forums/en/exchangesvrclients/thread/8b18c94b-5c2a-48ad-8ac0-06de12463f6b http://support.microsoft.com/kb/894435 Tim Harrington - Catapult Systems - http://HowDoUC.blogspot.com

The most possible cause is Enable32bitAppOnWin64 setting, as mentioned in the links from Tim Please following the steps in the “ASP.NET 2.0, 64-bit version” section of the KB 894435, which should fix the issue James Luo TechNet Subscriber Support in forum If you have any feedback on our support, please contact tngfb@microsoft.com Please remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.