If all of a sudden your network folders/ WebDAV accounts have stopped working after an SP2 upgrade to your Windows software it is actually a new "feature" from Microsoft. In SP2, all webdav accounts now require https secured connections by default (previously http only was the default). Unfortunately you do not receive an error message, the only symptom is that your login fails over and over.

WebDAV extends the HTTP protocol to allow users to publish, lock, and manage files on the Web site like a remote hard disk. This makes filesharing very easy as you are using HTTP traffic. In many ways it is considered the evolution of FTP.

Fortunately there are a few solutions.

1. 
   
2. add ":80" to the end of the domain name like "http://mysite.com:80" (assuming the webdavservice is on port 80). This tells webdav to use the old http login instead of requiring https.
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4. make a registry change to enable the old Authentication as described here (KB841215)
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6. install SSL security on the WebDAV site (which is really not a bad idea.)
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Another Microsoft problem is from a recent service pack update from Microsoft that limits the number of attributes per XML element to 32. More information on that fix can be found here (KB888164).

To make matters worse, there seem to be about 30 different versions of the WebDAV libraries floating about, changing based on the Windows software that you use. This site has a good list of the different versions and problems related to each of them.

Anyways, at least the WebDAV client still works but it is not quite as easy to use as could be expected.

Tags: webdav, Sharing, XP