Simple WebDav Server

I'm looking for a simple WebDav server solution. I'll explain my setup. I have a PC running XP pro. I connect to network shares located on a NAS. I need to give my clients access to specific folders inside their designated project folders, and I want to do it through WebDav. What I need is a WebDav server solution that would provide me with an interface in which I could select either a local folder or a network share (mapping a network drive is also acceptable for selection), and specify a username and password which the end user would have to provide in order to log into their web folder. An added bonus would be if I could create a .MSI or .EXE that would create a path to the Web Folder on my clients' machine. As I have an infinite number of projects, I'll require hundreds of Web Folders which can be accessed simultaneously through various logins. Of course no login would give access to another folder. MY clients will log into their web folders via windows xp. They will not be running a client program and installing software on their machines is not an option. Who can provide me with a solution?