That’s right! When you are starting your development machine, which is packed full of developer goodies (gtalk, skype, apache, mysql, mssql, tomcat, eclipse, etc) you will eventually face a scenario where something conflicts. Normally this swag of developer tools works in perfect harmony with eachother, however on some occasions lines are crossed, relationships are torn apart and war breaks out over port usage.
If the Apache process fails to boot prior to the skype process at system startup time, you may very well lose your 80 and 443 ports! Skype uses them to assist in incoming communications from other Skype users (as these ports are normally free on a ‘reasonable persons’ computer - and chances are that these ports would be less war-provoking from firewall applications.
So if you have Skype and your Apache fails to start due to port conflict, here’s how you fix it:
Skype -> Tools -> Options
Click on Advanced
Uncheck “use port 80 and 443″
Okay, so if you don’t have skype (and your on a windows machine) you can use:
(cmd prompt) C:\>netstat -lo
look for the PID that is using host:http as it’s port
fire up windows task manager (alt+ctrl+del, then task manager)
View -> Select Columns
Check “PID”
Look for PID # XXXX in your list
Fix/Kill that process.