If you are getting this error:
WebDAV 403 - Forbidden Access is denied. Server Error: 403 - Forbidden: Access is denied.You do not have permission to view this directory or page using the credentials that you supplied.
Here are the steps to solve it:
Make sure that your ntfs permissions is set for the user that is trying to connect to WebDAV
You need to create an Authoring Rules for the user that is trying to connect to WebDAV