Hi - I got it to work, and wrote a little help (which can be found in fullsize at my site: www.mdz.dk)
0)
Create a dir e.g. "c:\webserver\pages\area51"
Create a "index.html" file, and put in the dir! (very important)
1)
Create users and passwords with Apache´s own tool, which can be found in "\apache\bin\htpasswd.exe"
type "htpasswd -c c:\webserver\pages\area51\users.pw mads"
Now you´ll be prompted to type and retype a password.
To add more users into same users.pw - just skip the "-c" (create).
2)
in Apache´s httpd.conf you must allow Apache to use .htaccess-files.
Find two places with "AllowOverride None" and change them to "AllowOverride All".
3)
There can be problems for you or Windows handling files named ".htaccess" therefore
find in httpd.conf "AccessFileName .htaccess" and change it to "AccessFileName my.htaccess".
4)
In the directories where you want a validation before users can acccess your files,
you can now add a file named "my.htaccess" containing:
AuthName "My secret area"
AuthType Basic
AuthUserFile "c:\webserver\pages\area51\users.pw"
require valid-user
Satisfy All
5)
Now restart Apache, and if you have visited this page before, be sure
that you reload the page!
Greets Mads