Let’s look at how this was handled in Outlook 2013. I’ve seen plenty of people complaining about it on the Technet forums and elsewhere but I haven’t seen anyone getting a solution but I’ve found a few ways to solve the problem. This was easy to change in previous versions of Outlook but not in Outlook 2016. The reason is that the Exchange 2010 Autodiscover service tells the client to try a regular RPC/TCP connection before resorting to a RPC/HTTP connection. Again, Outlook 2010 does not recognize the MFA and still works with Exchange Online using basic authentication, but all other Office 365 services work fine with Office 365 MFA (both SMS and Authenticator authentication).With a default Exchange 2010 Outlook Anywhere configuration it takes around 30 seconds after Outlook 2016 startup before the client manages to connects to the Exchange server. The only workaround here was to temporarily disable MFA for my user account, create a new Outlook profile (which worked fine without MFA) and re-enable MFA. Since Outlook 2010 does not work with Office 365 MFA, especially not in a hybrid environment (not even with an App Password). This works fine for OWA and Office 365 ProPlus, but not for Outlook 2010. Last week I changed the MFA settings (see previous authenticator app for Office 365 blogpost). X-AutoDiscovery-Error: LiveIdBasicAuth:AppPasswordRequired: Īnd further down more details are revealed: This indicates that the user may not have logged on for the first time, or the account may be locked. Mostly this is caused by Autodiscover that goes wrong somewhere, the Remote Connectivity Analyzer shows that Autodiscover to the on-premises Exchange 2010 goes well, but that the redirect to Exchange Online goes wrong and it generates the following error message:Īn HTTP 456 Unauthorized response was received from the remote Unknown server.

After a minute the dreaded an encrypted connection to your mail server is not available error message appeared: Remove the Outlook profile but creating a new Outlook profile didn’t work. This morning my Outlook 2010 was working offline, and it didn’t want to go online (OWA and Outlook 365 ProPlus were working fine). And every Monday morning I run the Windows 7 VM for an hour or so to see if everything is working fine 😊 For testing purposes, I have two VMs, one with Windows 7 and Office 2010 and one with Windows 10 and Office 365 ProPlus. One of my clients is running Exchange 2010 in hybrid mode, and they have Outlook 2010 and Outlook 365 ProPlus client.

Outlook 2019 and exchange 2010