Hello

I already have a web server up and running, as htttp://www.mydomain.com
I'm not entirely sure of to turn this site to https://www.mydomain.com

My ultimate objective is to allow users to log on our website, with
user name and password, then let them either update a file to our
server or download a file from our server.

I'm using W2003 server SVP1 enterprise edition and the IIS 6 with this.
any help is great help, what's invloved, what I need to install...

Thanks
TT

First off, HTTPS means secure connection.  it does NOT mean that it is
password protected - those are completely different things.

When you go to any large/reputable site that accepts credit cards, you
will notice that during ordering you will jump to SSL.  (Secure Socket
Layer) You can tell by the "https" or the little key in the bottom of
the browswer (if you are using IE).    In order to provide SSL you
need to install a digital certificate on the server.  There are many
companies that will sell these or you can even generate your own (be
forwarned, that if you make your own, people might get warnings on
your site stating that you use a certificate that is not from a
'Trusted' certificate authority.

Your server uses the certificate to not only prove they are who they
say they are, but it also uses public key encryption to create a
secure connection (encrypted) between your browser and the server.

Now to log into the server, you can do it in many ways from integrated
with windows security - to coding it yourself with a database to
control access.
 
Here are some good resources to read
http://en.wikipedia.org/wiki/Certificate_authority
http://en.wikipedia.org/wiki/Secure_Sockets_Layer
http://en.wikipedia.org/wiki/HTTPS