BuddyPress.org

Almost certainly the way you have IIS configured, which is why I said at outset it’s hard to help.

Not sure as I can’t recall how we had our IIS servers set up but this doesn’t feel like the correct document root necessarily ‘netpub\wwwroot’  or at least in there you should be setting up site folders. Have you configured local development domain names in your hosts file to make life easier and corresponding folders under ‘wwwroot’?

Is the site otherwise performing in all other respects correctly?