This is an issue with Logins to C&C list which are made via HTTP-Fast (80) are currently failing. This will be fixed with TV 14, it would already work with the insider, since this will use the router login.
In the current version 13, you would need to create below registry key as a work around.
For version 10 and higher use the following path: 32 bit: HKEY_LOCAL_MACHINE\SOFTWARE\TeamViewer 64 bit: HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\TeamViewer
DWORD registry key "AllowedConnectionProtocols" with the value of 12:
For version 9 and older use: 32 bit: HKEY_LOCAL_MACHINE\SOFTWARE\TeamViewer\Version? 64 bit: HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\TeamViewer\Version? DWORD registry key "AllowedConnectionProtocols" with the value of 12: HTTP = 1 HTTPFast = 2 Port443 = 4 TCP = 8
The value for AllowedConnectionProtocols is created by adding the values for each of the protocols that should be enabled. e.g.: HTTP and HTTPFast can be disabled now with AllowedConnectionProtocols = Port443 + TCP = 4 + 8 = 12.
(*Also possible: if you want to disable only one connection protocol to subtract the number from 15)
We apologize for any inconvenience this may cause.
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