WampServer

I Had this same issue, My OS is 8.1 x64 All I needed to do was: wampmanager -> Apache -> Version -> now click on the Apache version number menu. this forced a windows allow Apache access conformation box. As soon as I gave Apache run access my problem was fix. if this doesn't work since your on VISTA try restarting wampmanger and run as "admin"
Forum: WampServer English