Exchange 2013 SP1 in a 2 member DAG. We have some users getting the logon prompt multiple times while outlook is running. These clients are using outlook 2007. My understanding is you will get the login prompt once when you open outlook. Here is a pic of the login box. Notice this box is connecting to autodiscover.domain.tld (shouldn't it be domain.tld?):
I have set OA auth method from negotiate to NTLM. Should that fix the many login pop-up boxes?