The Exchange Web Service (EWS) is the web service that allows access to the Out of Office service. If either the internal or external URL for the EWS is missing or incorrect, OOF will fail and other services may not work as expected.
Using Exchange Management Shell, check the URLs assigned to the web service virtual directory using the Get-WebServicesVirtualDirectory command. If either the internal or external URL is missing or incorrect, set them using the Set-WebServicesVirtualDirectory command.
Get-WebServicesVirtualDirectory
Type or paste this line into Exchange Management Shell to check the EWS URLs
Get-webservicesvirtualdirectory | fl identity,internalurl,externalurl
If the server is configured correctly, the command returns results similar to the following, with URLs in both the InternalUrl and ExternalUrl fields.
Identity : Server_name\EWS (Default Web Site)
InternalUrl : https://server_name.your_domain.com/EWS/Exchange.asmx
ExternalUrl : https://owa.your_domain.com
Set-WebServicesVirtualDirectory cmdlet
If the external URL is missing, set it using the Set-WebServicesVirtualDirectory command:
Set-WebServicesVirtualDirectory -Identity “Server\EWS (Default Web Site)” -InternalURL https://server_name.your_domain.com/EWS/Exchange.asmx -ExternalURL https://owa.your_domain.com -BasicAuthentication:$true
Verify the server names are correct by running Get-WebServicesVirtualDirectory | fl identity,internalurl,externalurl again
(Remember to replace the server names in the Set-WebServicesVirtualDirectory command with the correct server names for your organization.).
Links
Get-WebServicesVirtualDirectory
http://technet.microsoft.com/en-us/library/aa998810(EXCHG.140).aspx
Set-WebServicesVirtualDirectory
http://technet.microsoft.com/en-us/library/aa997233(EXCHG.140).aspx
More Information
Outlook 2007 Out of Office Failure (EMO, 8/14/2008)
Overview of the Autodiscover Service
A new feature is available that enables Outlook 2007 to use DNS Service Location (SRV) records to locate the Exchange Autodiscover service