Giving credentials to the pop-up, everything is ok. The problem was much discussed during the Preview phase of Office for Mac 2016 but never corrected. This refers to the constant pop-ups that make it appear like Outlook is forgetting your password every few minutes, etc. Now when we activate the Exchange 2016 Servers, I mean all the Url's pointing to Exchange 2016 Servers, the 2010 Mailbox Users get an Outlook prompt, not the Exchange 2016 MBX Users. As we know, one of the biggest bugs in Outlook for Mac 2016 is the ever-so-annoying repeated password prompt problem.
We changed all the Outlook connection prior to install Exchange 2016 to Outlook Anywhere - everything worked fine. The reason for this was an ambigous URL problem we had to solve. We had to activate Outlook anywhere on the Ex2010 Servers and to force all Outlook Clients to use Outlook anywhere. We haveĮnabled Outlook Anyhwere on the Exchange 2010 Servers and configured also the clientauthentication method for these Ex10 Servers following the Deployment Assistant (Clientauthentication -> Basic, IISAuthentication ->NTLM,Basic). We have configured the Exchange coexistence and infrastructure according to the Exchange Server Deployment Assistant from Microsoft. We have a coexistence Scenario with 2 Exchange 2010 servers (CAS/HUB/MBX) and 2 Exchange 2016 servers.
