Outlook for MAC 2011 Kerberos with Exchange 2013

Hi guys,

I've been sent here from the Technet guys where you can find my original question: Exchange 2013 Kerberos with Outlook for MAC 2011

For everyones convenience I list the details of the case again:

I'm in the process of deploying a domain from scratch for my company because we have to get rid of the single label domain we are using right now.

Here are some Facts:

• We have 3 offices in 2 countrys, connected through IPsec VPN
• One internal domain: abc.lan
• One external (email) domain: abc.com
• Every office has one DC and one Exchange 2013 SP1 Server at the moment.
• ALL internal AND external Exchange URLs of all 3 Exchange Servers use mail.abc.com in order to keep SAN requirements low additionally this is basically DNS round robin
  
• I have deployed Kerberos according to this article Exchange 2013 - Configure the Client and Kerberos (load balancer or DNS round-robin) access (it's a french article so you need to translate it in your language via google or something)
• The MAC Clients can domain join without any problems and access SMB shares with "single sign on"

The Problem:
With Outlook 2007, 2010 and 2013 Clients everything is working perfectly. But on Outlook for MAC 2011 I have the issue that when I configure the mailaccount with Kerberos authentication, I get the Message: "This Exchange server does not use Kerberos authentication. Click OK to turn off Kerberos authentication".

I checked "klist" in terminal and the required kerberos ticket is present: http/*** Email address is removed for privacy ***

Strange behaviour here is, that Outlook says it is "Connected to Exchange". But neither the sync/send mail is working nor the public folders are.
Another strange thing is that if you wait 5-10 minutes, everything is working flawlessly.

Does anyone have an advice?
According to the proposed Answer of this Outlook 2011 for Mac - cannot use Kerberos thread the problem is that kerberos does not work with EWS external URL. Which is fine because I only need to use it internally but since both external and internal URLs are the same, this could maybe confuse the not that sophisticated Outlook for MAC client. Can anyone confirm that?
I know that kerberos is not working from outside the network. This test is only focusing on clients that are within the LAN.

When you troubleshoot connection issues in Outlook on Windows you can CTRL+Click on the taskbar icon of outlook and go to "Connection Status" or "Test E-Mail AutoConfiguration" which saved my rear end quite often by now. Is there something similar on MAC?

Any suggestion is greatly appreciated. :)

Best greetings,
Vasko