As we have been testing Office 2013 with our Office 365 implementation, we ran into two issues.
#1 – Lync 2013 could not sign in and we would receive an error message stating “Cannot sign in because the server is temporarily unavailable”. After digging through a lot of different forums and support threads, the one workaround that worked reliably was to launch Lync as a different user that was local to the computer and not on the domain. While this works for IT folks, not a permanent solution for the entire company.
#2 – When trying to access SharePoint documents or otherwise interact with Office 365 through Office 2013, we would get authentication prompts that would state “Call us overprotective, but we need to verify your account again before opening this document.” These we could not find a reliable workaround to. Many-times a document from SharePoint simply could not be opened/edited due to the prompt displaying over and over again.
We ended up opening a ticket with Microsoft for each of these issues. While troubleshooting the issue we were doing packet captures and analyzing the packet captures when we noticed a number of TCP resends which looked similar to an issue we were having with downloading larger files from SharePoint Online. (Side note: If you are battling SharePoint download issues as well, this will help identify the issue…) The fix/workaround that we found for that solution was to disable AutoTuning in Windows 7.
We tested disabling AutoTuning and like magic both of these issues went away we could sign into Lync 2013 and we could successfully authenticate when the Overprotective prompt comes up.
To disable AutoTuning, from an elevated command prompt (right click on cmd.exe or command prompt and choose run as administrator) execute the following command:
netsh int tcp set global autotuninglevel=disabled
For best results reboot your computer.
We are still working with Microsoft to determine what in our network layer would be causing this. For reference we are a Cisco shop, if this fixes your problem would love to hear what your core network vendor is.
Note: Our configuration provides WS-Fed through a Cloud Identity Management Solution. We utilize our Active Directory Domain for authentication to Office 365 through this service.