I rebooted my exchange server in the normal course of applying a antivirus update. and now i am getting the following error when trying to open OWA. Outlook Web Access did not initialize. An event has been logged so that the system administrator can resolve the issue. Please contact technical support for your organization. Request Url: https://mail.eleosdata.com:443/owa/auth/error.aspx?url=https://mail.eleosdata.com/owa/&reason=0 User host address: 10.10.101.138 Exception Exception type: Microsoft.Exchange.Clients.Owa.Core.OwaInvalidConfigurationException Exception message: Object reference not set to an instance of an object. Call stack Microsoft.Exchange.Clients.Owa.Core.OwaConfigurationManager.CreateAndLoadConfigurationManager() Microsoft.Exchange.Clients.Owa.Core.Globals.InitializeApplication() Microsoft.Exchange.Clients.Owa.Core.Global.ExecuteApplicationStart(Object sender, EventArgs e) Inner Exception Exception type: System.NullReferenceException Exception message: Object reference not set to an instance of an object. Call stack Microsoft.Exchange.Clients.Owa.Core.Configuration.CheckPublicFolders(ADSystemConfigurationSession session, ADObjectId[] pfdbIds, Boolean& allLegacy, Boolean& allLater) Microsoft.Exchange.Clients.Owa.Core.Configuration..ctor(ADSystemConfigurationSession session, String virtualDirectory, String webSiteName, ADObjectId distinguishedName, Boolean isPhoneticSupportEnabled) Microsoft.Exchange.Clients.Owa.Core.OwaConfigurationManager.LoadConfiguration() Microsoft.Exchange.Clients.Owa.Core.OwaConfigurationManager.CreateAndLoadConfigurationManager() Based on blogs and posts this is what i have done so far? *deleted and then recreated the exchange 2007 virtual directories, below is output of current virtual directories: Name Server OwaVersion ---- ------ ---------- Exadmin (Default Web Site) DTCEX01 Exchange2003or2000 exchange (Default Web S... DTCEX01 Exchange2003or2000 public (Default Web Site) DTCEX01 Exchange2003or2000 Exchweb (Default Web Site) DTCEX01 Exchange2003or2000 owa (Default Web Site) DTCEX01 Exchange2007 * then did an iisreset, still getting the error. Im pretty sure this has something to do with the virtual directories and or permissions issue. any assistance would be greatly appreciated! *i ran the exchange BPA (permission and connectivity) and no overt issues were found. marlon

If you're not on the latest SP and RU, may be worth apply that and checking if the issue is resolved. I assume this is on the Exch server itself as well as clients?Sukh

If you're not on the latest SP and RU, may be worth apply that and checking if the issue is resolved. I assume this is on the Exch server itself as well as clients?Sukh

I cannot remember which one, but there was a 2007 UR that had this issue. Please install the latest SP/UR and see if that takes care of it.

Thanks for the Advice. Will apply the latest SP and UR and see if that corrects the issue and post back.marlon

Hi If your problem is solved by Updating to latest SP and RU, Please Mark Above Thread As Answer and Finish this issue Also, if you have any further questions, dont hesitate asking here CheersZi Feng TechNet Community Support

Unfortunately applying sp3 did not fix the issue. Any more assistance would be greatly appreciated.marlon

Did you also apply the latest rollup? I think the issue may be related to IIS which may need to be reinstalled or worse case a reinstall of the CAS role.Sukh

Did you also apply the latest rollup? I think the issue may be related to IIS which may need to be reinstalled or worse case a reinstall of the CAS role.Sukh