How do I enable single sign-on (SSO) for WebDAV access?

Users will not be prompted for authentication when they access SharePoint through a WebDAV interface. To enforce SSO to WebDAV you have to modify the computer’s registry by following these steps or by applying a group policy for this setting:

  1. Open your computer’s “Registry Editor” (click on the computer’s start button and type “regedit”) and start the application.
  2. Locate and then click the following registry sub-key: “HKEY_LOCAL_MACHINESYSTEMCurrentControlSetServicesWebClientParameters”
    HKEY_LOCAL_MACHINESYSTEMCurrentControlSetServicesWebClientParameters
  3. Right-click the “Parameters” key and select “New”, and then “Multi-String Value”:
    Create a Multi-String Value key
  4. Type “AuthForwardServerList”, and press the “Enter” key on your keyboard:
    Name it AuthForwardServerList
  5. Right-click the “AuthForwardServerList” values and select “Modify…”:
    Modify AuthForwardServerList
  6. In the Value data box, type the URL of your SharePoint domain, e.g. “https://contoso.sharepoint.com” and then click on the “OK” button:
    Add the URL of your SharePoint domain
  7. Close your “Registry Editor”.
  8. Restart the computer’s WebClient service (or the computer)
    1. Open your computer’s “Services” (click on the computer’s start button and type “services”) and start the application.
    2. Go to the WebClient service, right-click it and select “Restart”:
      Restart the WebClient service
  9. You should also add both of these domains to the same security zones, the “Trusted sites” zone, see recommended browser settings for more information:
    1. https://login.microsoftonline.com
    2. https://[tenant’s-name].sharepoint.com