During the installation of Apache2 I got the following message into cmd window:
Installing the Apache2.2 service The Apache2.2 service is successful
I've had this problem twice. The first problem was fixed using the marked answer on this page (thank you for that). However, the second time proved a bit more difficult.
I found that in my httpd-vhosts.conf file that I made a mistake when assigning the document root to a domain name. Fixing this solved my problem. It is well worth checking (or even reverting to a blank copy) your httpd-vhosts.conf file for any errors and typo's.