We use an F5 load balancing device in our Exchange environment. It is assigned the DNS name "Outlook". The F5 load balances between two CAS Exchange servers, "ServerA" and "ServerB". We also use the Exchange AutoDiscover service and have it direct the clients to the F5 device "Outlook" for load balancing.
For most clients AutoDiscover works great and points the users to the F5 device "Outlook". On some clients the autodiscover points to client directly to the CAS "ServerA" instead of "Outlook".
The same user can log onto a different workstation and the autodiscover will correctly point to "Outlook". All clients use outlook 2007 or Outlook 2010.
We need ideas on what is causing some clients to get "autodiscovered" directly to the Exchange Server instead of the F5.