Permission Error on Server

Hello, I have (I think) a functioning Apache server on Windows, and I have
set up some aliases. Now, the problem is, when I type the url
'localhost/c:/twiki/bin/configure', I get the message 'You don't have
permission to access /bin/configure on this server.'
I think this is a windows problem, but I'm a total newbie to Apache, so how
do I solve the problem (this file should get me to a script I want to run).