The background to this is that I recently installed SP2 for Exchange 2007 and it broke email syncing with all of my BIS blackberrys. I was finally able to resolve that and in the process I also installed an SSL cert for OWA to replace the self signed cert that we had been using (that's not what fixed the blackberrys by the way, just one variable I wanted to eleminate). I don't think this is relevant but the SSL cert is only valid for the OWA address and not for autodiscover. After getting the blackberrys working, and installing the cert, I made some changes to the URL's used for autodiscovery in order to remove cert errors for Outlook clients. So now everything seems to work. However I get two recurring errors on the exchange server that I can't seem to track down.This is the only exchange server in the environment and it runs CAS, HT, and MB. Exchange 2007 SP2First error pops up several times per hour:Event Type: ErrorEvent Source: MSExchange Web ServicesEvent Category: Core Event ID: 11Date: 2/23/2010Time: 5:18:03 PMUser: N/AComputer: <PainInMyArse>Description:CAS server <PainInMyArse> failed to proxy EWS to AD site CN=<localADsite>,CN=Sites,CN=Configuration,DC=<MyDomain>,DC=local because none of the CAS servers in this site are responding. Please check the configuration and status of the servers in site CN=<localADsite>,CN=Sites,CN=Configuration,DC=<MyDomain>,DC=local For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.I don't know what is generating this because as I mentioned we have only one exchange server in the environment. Plus it is in the same site that it seems to be trying to proxy to.Second error pops up less often, maybe a few times a day:Event Type: ErrorEvent Source: MSExchange Web ServicesEvent Category: Core Event ID: 15Date: 2/23/2010Time: 5:13:00 PMUser: N/AComputer: <PainInMyArse>Description:Client Access server "PainInMyArse" attempted to proxy Exchange Web Services traffic to Client Access server "PainInMyArse.MyDomain.local". This failed because the authentication for the connection between the two Client Access servers failed. This may be caused by one of the following configuration problems: 1. The host name in "PainInMyArse.MyDomain.local" may not be registered as a service principal name (SPN) with Kerberos authentication on the target Client Access server. This usually happens because you used the IP address, instead of the host name, of the target Client Access server in the internalHostname parameter for the Exchange Web Services virtual directory on the target Client Access server. You can change the internalHostname parameter for the target Client Access server by using the Set-WebServicesVirtualDirectory cmdlet in the Exchange Management Shell. If you do not want to change the internalHostname parameter for the Exchange Web Services virtual directory on the target Client Access server, you can use the "setspn.exe" tool on the target Client Access server to register additional SPNs for which that Client Access server will accept Kerberos authentication. 2. The server that is hosting "PainInMyArse.MyDomain.local" may be configured not to allow Kerberos authentication. It might be set to use Integrated Windows authentication for the Exchange Web Services virtual directory, and also configured to use only NTLM authentication (not Kerberos) for Integrated Windows authentication. If you suspect that this is the cause of the failure, and you need more information about troubleshooting, see the Internet Information Services (IIS) documentation. For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.So this error appears to be saying that the server is trying to send proxy traffic from itself to itself just using the FQDN for one name and the server name for the other.

Hi, Please try to use “Get-WebServicesvirtualdirectory |fl” and then post here. Please try to use “test e-mail autoconfiguration” from Outlook and then post here. Please try to browse the “Availability services URL” from IE and let me the result. What does Exchange 2007 Availability Service do? http://msexchangeteam.com/archive/2006/10/23/429296.aspx Configure Exchange Services for the Autodiscover Service http://technet.microsoft.com/en-us/library/bb201695.aspx Regards, Xiu

I had an opportunity to reboot the exchange server yesterday so I took advantage of it and did a reboot. When I went to reboot I also saw that rollup 2 for Exchange 2007 SP2 had been downloaded and was awaiting installation so I installed it and rebooted. The errors mentioned above have not returned since. So I don't know if it was the update or the reboot that corrected it but it seems to have resolved.