User Configuration > Administrative Templates > Microsoft Office 2016 > Miscellaneous
User
HKCU\software\policies\microsoft\office\16.0\common\sharepointintegration
This policy setting allows you to remove the Learn more about SharePoint hyperlink from the Save to SharePoint form in the Backstage view for Word, PowerPoint, Excel, Visio, and Project. If you enable this policy setting, the hyperlink will not be displayed. If you disable or do not configure this policy setting, the hyperlink will appear for the Save to SharePoint form in the Backstage view when there are no locations listed.