Please, help with WebDav and IIS 6

 I am having some dificulties with WebDav in IIS 6 in a 2003 server and I am thinking am missing some setup. Here is the behaviour:

-I have a virtual directory in the default site that I have set up as webdav linked to a directory in the internal drive. I have tried all kind of athorization and even anonimous access. The permisions for the directory are allow all for administartors, users of the domain and even for everyone. The address would be like http://server/webdav.

--From windows 7, I can access the webdav maping it to a drive letter (the way I need it). Once it is mapped it shows the path '\\server\DavWWWRoot' though.

-From XP pro or server 2003 I can access the webdav as a webfolder in my network places, from an internet browser but it refuses to map it as a letter either with the net use command or using the Tools/Map network drive interface. It always return the error ' The network path http://server/webdav could not be found'. The same path works for web folders and any browser and it is my understanding that it is not the root of the server.

Now, the anoying bit: I have set up a webdv folder in another XP pro machine with an IIS 5.1 in the same way that I did in the IIS 6 2003 server.

-All works as I was expenting and windos 7, XP and 2003 can map the webdav directory as a network drive straight away and use it from any program. Which makes me feel that I am missing some configuration in the IIS 6?

The port 80 is of course open and if I wireshark the packets, it just stops communication and rises the error after the server aknowledges http/1.1 200 ok. There is one more packect from the client to the server and that is all.

I have been trying to find some light into this and have spent few days googling but no muc success.

Please, any advise?