I have a user that has a Lenovo laptop with Windows 10 Pro and Outlook 2016 Home & Business. Their office uses SBS 2011 with Exchange 2010 Standard.
I setup this laptop about 2 or 3 months ago, and since about two weeks the user cannot connect with Outlook when outside of the office. For instance if the user is at home and they attempt to open outlook it asks for the password, but does not accept it. The user account is not locked and I confirmed the password is correct by logging onto OWA without issue. I also deleted all Credential Manager entries just in case. I also created a new Outlook Profile. I confirmed the Outlook account does not have Prompt for password under the Security tab.
So, the only way Outlook accepts her password and updates is if she invokes a VPN connection. Once the VPN is up then she can successfully log onto to Outlook and work without issue. I also believe the laptop is fully patched with the exception of the Creator's October update.