[horde] ActiveSync and Windows 8 Mail App

[Jonas Ryser]

Hi,

I'm trying to set up horde 5.1 with ActiveSync. I got it working with MS Outlook 2013 but not yet with the Windows 8 Mail/Calendar/Contacts App. 

When I try to add the ActiveSync Account to the Windows 8 Apps I get an error message saying that it can't connect to the server. In the ActiveSync log on the server I get the following for each try to create the account: 

---
2013-10-07T14:11:36+00:00 INFO: [9072] Horde_Core_ActiveSync_Driver::authenticate() attempt for jonas
2013-10-07T14:11:36+00:00 DEBUG: [9072] OPTIONS request received for user jonas
2013-10-07T14:11:36+00:00 INFO: [9072] Device entry exists for CB2BD6D6AA52705EB59E315EA9EBB7F1, updating userAgent and version.
2013-10-07T14:11:37+00:00 INFO: [9072] User jonas logged off
2013-10-07T14:11:37+00:00 INFO: [9073] Horde_Core_ActiveSync_Driver::authenticate() attempt for jonas
2013-10-07T14:11:37+00:00 DEBUG: [9073] OPTIONS request received for user jonas
2013-10-07T14:11:37+00:00 INFO: [9073] Device entry exists for CB2BD6D6AA52705EB59E315EA9EBB7F1, updating userAgent and version.
2013-10-07T14:11:37+00:00 INFO: [9073] User jonas logged off
2013-10-07T14:11:38+00:00 INFO: [9073] Horde_Core_ActiveSync_Driver::authenticate() attempt for jonas
2013-10-07T14:11:38+00:00 DEBUG: [9073] OPTIONS request received for user jonas
2013-10-07T14:11:38+00:00 INFO: [9073] Device entry exists for CB2BD6D6AA52705EB59E315EA9EBB7F1, updating userAgent and version.
2013-10-07T14:11:39+00:00 INFO: [9073] User jonas logged off
---

Because Outlook 2013 works perfectly I think Apache and Horde are configured correctly. 

I have no idea where to start to find a solution. I read somewhere that sniffing the traffic using WireShark might be interesting, but I can't do that because the Windows 8 Apps require SSL. I don't know any way to get the Windows 8 Apps giving a more detailed output. I tried also WIndows 8.1 preview with no success. 

Any idea where to start? 
Thank you! 

Jonas