Exchange 2010 Mailtips not working with Outlook Anywhere users?
Today I fixed an issue where Outlook 2010 clients via Outlook Anywhere didn't get Mailtips, but OWA, internal and users connecting via VPN did get them.
Mailtips are using the EWS IIS virtual Directory. As ISA 2006 was used (and it does not have Exchange 2010 wizard as I recall), I checked whether EWS was allowed by the publishing rule. It was.
Also I checked the ExternalURL, most of the time this would have to be the same as the external webmail URL. You can do that with Get-WebServicesVirtualDirectory
If the ExternalURL is correct, it could be that it is an authentication issue with the EWS folder. Depending your architecture, it is possible that Basic authentication is necessary (for instance using a reverse proxy and/or in combination with SSL).
Check this in the Exchange shell with:
Get-WebServicesVirtualDirectory| fl *auth*
Which gives something like this:
CertificateAuthentication :
InternalAuthenticationMethods : {Ntlm, WindowsIntegrated, WSSecurity}
ExternalAuthenticationMethods : {Ntlm, WindowsIntegrated, WSSecurity}
LiveIdSpNegoAuthentication : False
WSSecurityAuthentication : True
LiveIdBasicAuthentication : False
BasicAuthentication : False
DigestAuthentication : False
WindowsAuthentication : True
So, we see that there are authentication methods enabled. WindowsAuthentication is enabled, which explains the behaviour of internal and VPN Outlook users. OWA users work somewhat differently, they themselves do not need direct access to the EWS folder. As said, there is a ISA server in front of the Exchange server, so Basic authentication would probably be necessary.
Enable the required authentication method with:
Set-WebServicesVirtualDirectory -identity "SERVERNAME\EWS (default Web site)" -BasicAuthentication $true
Change SERVERNAME accordingly. In this example case Basic authentication was enabled.
After this Mailtips worked for everyone!