Unable to map a SharePoint site as a network drive

I am running WSS 3 on a Windows Server 2008 and want to map my site from ie Word or the explorer. But I get the message “Network path not found”:

Or if I try to map to it or if I run “Net use” from inside the command prompt. I get the following message:

“C:Userslise.rasmussen>net use x: http://xxx.com/Shared%20Documents/
Enter the user name for ‘xxx.com’: domainloginname
Enter the password for xxx.com:
System error 67 has occurred.
The network name cannot be found.”

So I cannot open my site directly from the Explorer (via Map Network drive) cause then I get this message (“The folder you entered does not appear to be valid. Please choose another”):

Or in Explorer View from SharePoint, then I get this message (“Your client does not support opening this list with Windows Explorer”, and yes it is from the client, not the server):

I run a Windows Vista client, and the client service is installed. And one more thing, if I open a document from the site I get THREE login prompts before I can open the document. I can only press Esc but… how irritating isn’t that!!

The Desktop Experience is installed on the server, as well as WebDAV and it is rebooted. I also checked that the AAM is correct and can be reached from the server, check to that 🙂

Some blogs suggest that you update the Web Folders, but that are for really old browsers and stuff… Don’t want to do that this early. That will have to be a backup plan..

I googled it many times but have not found a solution that works for me…