Securing FTP access in IIS 4.0

I want to set up IIS so that I get a secure connection to a users home directory.
At the moment, I have ftp set up so that a user logs on to the ftp site and by using their alias get access to their home directory.
However, ftp is unencrypted and when I specify the home directory share for the virtual directory file location, I have to specify a username and password for this resource.
I would prefer that IIS passed through the username and password to the network resource to tighten up security.
I’m also going to have to find a way of automatically creating a virtual directory for all of the 500+ user accounts in our organisation. Can this be automated.

Any help with this would be greatly appreciated.

Regards,

Paul Kellett