Disable TeamViewer from "stealing" Port 80?

Did you enable the Direct-In Modus? You can disable it in

   Options > Advanced > Network > TeamViewer DirectIn check

From the manual, page 59 (PDF):

Check Opens a dialog where the availability of TeamViewer is checked. The DirectIn Ports 80 and 5938 do not have to be opened , however, TeamViewer can use these ports - if available - for establishing faster connections.

Options > Advanced > Show Advanced Options > Don't use incoming ports 80 and 443

1. Open port 5938 (TCP) on your firewall.

2. Change the following registry keys.

   • [HKEY_LOCAL_MACHINE\SOFTWARE\ TeamViewer\Version4] Key ’GatewayAllowed’ set to 0 * [HKEY_LOCAL_MACHINE\SOFTWARE\TeamViewer\Version4] Key ’ListenHttp’ set to 0

On the new teamviewer you go to advanced settings and then Don't use port 80

If you are using Windows 7 x64, you will find that the registry keys are in a different location. I have searched the registry and cannot find anything along the lines of 'GatewayAllowed'. The other key is as follows:

HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\TeamViewer\Version6\ListenHttp