|Hi, if it's just for that, why don't you just activate your IIS? It's a lot easier than installin apache.|
look in control panel -> add/remove programs -> add remove windows component -> (expand) internet information service -> (check) worldwideweb service.
Have the CD ready and click next next next
Then assuming your port 80 isn't blocked by your ISP, you can tell people to type http://youripaddress/ to access files in your c:\inetpub\wwwroot\ (you can delete all files in this folder safely, otherwise it'll have some confsing pre-built website)
Then you can play with the settings in: (right click) MyComputer -> Manage -> services & applications
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