Windows WebDAV Clients

There are four ways to access WebDAV folders from Windows. Not all methods are available on all versions of Windows.

1. (Preferred) Use the Add Network Place wizard. Enter the URL of the folder e.g.

   http://server/dav

2. Mount a WebDAV folder on a drive letter from the command-line (a DOS box).

   C:\> net use * http://server/dav
   Drive Z: is now connected to http://server/dav.

3. Via Internet Explorer (IE 7 or earlier), by following the File->Open menu and selecting "Open as Web Folder". Enter the URL of the folder e.g.

   http://server/dav 

4. Directly from an application, such as Microsoft Office. Type the full URL path to the document e.g.

   http://server/dav/System/AccessControl.txt

Some of the above methods may not work on some versions of Windows, or when using SSL, or with some types of authentication. These problems are not unique to this WebDAV implementation; the bugs are in the clients, not the server.

• For example, using WindowsXP service pack 2, "Open as web folder" results in a standard windows share style authentication dialog which fails (doesn't even send a request to the DAV server), and then when you hit cancel, a different login dialog pops up - entering your Foswiki username and password here works

See http://greenbytes.de/tech/webdav/webdav-redirector-list.html and http://greenbytes.de/tech/webdav/webfolder-client-list.htmlfor a list list of the known bugs in different Windows versions.

Depending on what version of Windows you are running - and how you access your files - then there may be up to four different implementations of DAV used. Due to the wide range of Microsoft platforms, it has not been possible to test all of these implementations, and all those tested have known bugs. In general, Windows XP and later attempt to connect using a component called the WebDAV Mini-Redirector, except for when files are accessed from Microsoft office in which case the Microsoft Data Access Internet Publishing Provider DAV is used. When reporting problems it is critical that you identify which of these methods is being used to access WebDAV, by running the server with full tracing enabled.

Problems with authentication

By default the WebDAV Mini-Redirector will not talk to Basic authentication. This is because Basic Authentication is very insecure over a plain connection. If your server uses SSL, or you are behind a corporate firewall, you may consider it safe to enable it by following the instructions at http://support.microsoft.com/kb/841215

Windows caches authentication aggressively. This is usually not a problem unless you try and change authentication method, in which case rebooting Windows usually works, though you may have to explicitly clear your caches as well.

If a single folder is mounted on a server using DAV, the WebDAV Mini-Redirector assumes that the root folder on the same server is also mounted using DAV, and will try to apply the same cached authentication to all sub-folders; so having two sub-folders on the same server with different authentication schemes won't work. This applies to all folders mounted via WebDAV from a single server.

If you want to use Digest authentication, you will have to log in with an NTLM domain name (e.g. CORPORATE\myname). The NTLM domain string is required in the server password file (so Foswiki user myname needs to be in the digest file as CORPORATE\myname).

Problems with Microsoft Office

After opening a WebDAV document in Office, you may see the message "Contacting the server for information. Press ESC to cancel." in the application status line. Office does not attempt to open any connections to the WebDAV server after an initial PROPFIND. Clicking ESC results in the message "Downloading ..." which again does not open any connections. Eventually after some minutes the application may display the document, with no further communication to the WebDAV server. Research on Google suggests that this is a bug with the printer driver in Office.

If the server does not support authentication, or if there have been other problems with communication, the Office will open documents in "read-only" mode.