Teamviewer uses port 80 by default to connect which causes issues with localserver if not configured on any other port.
When windows start, teamviewer waits a couple of minutes before it starts listening to port 80. If the port is not taken already by any other application, it starts using it.
If the application / server does not start before teamviewer, teamviewer will take the port 80 and once other application is run, it will give error. If you try opening localhost from the browser after running the apache or other server, it will give this error message:
This site is running TeamViewer
To disable this behavior in TeamViewer version 5.1 or higher follow these steps:
- Launch teamviewer
- Goto Extras > Options
- In options window goto Advanced tab
- Enable the option “Don’t use incoming port 80”
This will prevent teamviewer from listening to port 80 and thus conflicting with any other application that you need to listen to port 80 too and there will be no more “this site is running teamviewer” error.