So a recent virus infection ended up with me wiping my windows computer and reinstalling everything. While I was in the process of getting everything I use up and working again I encountered this error message while trying to install the "Apache HTTPD" webserver.
A quick google search turned up a couple of different possible culprits and a quick process of elimination identified that the skype app was to blame. Turning it off (not just logging out) allowed me to then get apache httpd installed and running.
What I don't get is why this error is thrown. Once installed as a service httpd and skype both work fine on the same machine. Oh well, the joys of working with computers.