Online CRM 2016 - Error occurred when I clicked on Document Management Settings.

Hi all,

I am facing an error trying to integrate Online CRM and Online Sharepoint which I hope someone can help me resolve.

After successfully setting up a default site in Settings -> Document Management -> SharePoint Sites, I clicked on Settings -> Document Management -> Document Management Settings to set up the folders for our custom entities and I got the following error:

Error

An Error has occurred.

Try this action again. If the problem conttinues, check the Microsoft Dynamics 365 Community for solutions or contact your organization's Microsoft Dynamics 365 Administrator. Finally, you can contact Microsoft Support.

This feature was working fine before.  Then suddenly I get this error when I click on Settings -> Document Management -> Document Management Settings.  Even after I deleted the SharePoint Sites record and setup the Configure Server-Based SharePoint Integration again, I still get this error when I click on Settings -> Document Management -> Document Management Settings. 

Please help !!!

Dzung.