Yesterday morning I opened Outlook and it worked fine. At some point during the morning it disconnected and stopped updating. I would notice emails on my phone but not in my inbox. When I closed and reopened, it requested me to log-in but does not recognize my password.
Now, when I open Outlook, I see all my emails and folders that were there prior to the disconnect, but in the lower right corner it says, "Last synced 1/10/17 8:04 am. Not connected...".
I get the log-in screen that has my email pre-populated for my Office 365 account. I add my password, hit enter, it appears to be logging-in, the screen goes away and within seconds it opens again with my email and a blank password field. This is repeated every time I try to log-in.
My 365 account, email, etc. still work with my login and password via a web browser. This is only a problem with Outlook. It should be noted that yesterday I did not perform any updates. All this began randomly.
I run Outlook on a Mac that is up to date, macOS Sierra 10.12.2
We use the Outlook log-in screen that is customized for our company.