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It appears there are a couple of different applications that can cause this same problem;
- IIS is still running.
- SQL Server Reporting Services is running.
- Web Deployment Agent Service is running (this was my problem).
To fix my issue (number 3), I followed the following procedure:
- Open up the services screen (Right click "Computer" from either your desktop or start menu, then "Manage". Once the window has opened, expand "Services and Applications" and select "Services").
- On the services screen there should be one called "Web Deployment Agent Service", if this is running, double click it and stop the service.
- Finally, change the startup type to "Disabled".
Now if you try to run apache on port 80, it should start fine!
No meu caso, deixei os serviços de relatórios em execução e desliguei o problema.