Consider the following scenario. You have a web site configured to use the WebDAV functionality of Internet Information Services (IIS) 7.0 or 7.5. You configure the website to use Anonymous authentication, and you configure the WebDAV Authoring Rules to grant Write access to all users. When you attempt to copy or move a file to the WebDAV directory by sending an HTTP PUT command, the operation fails. You may see an error message similar to the following, depending on the HTTP client you are using:
An error occurred copying some or all of the selected files.
HTTP 401 - Unauthorized
This behavior is by design. Beginning in IIS 7.0, anonymously writing to a WebDAV publishing directory is not allowed. Specifically, the PUT, MKCOL, PROPPATCH, COPY, MOVE, DELETE, and WebDAV-based GET requests all require authentication.
To allow users to write files to a WebDAV publishing directory, you must configure the directory to use an authentication method other than Anonymous authentication. For more information on configuring authentication types in IIS 7.0 and 7.5, please see the following document:
Configuring Authentication in IIS 7