Query ICS external adapter on Windows 10 or 11

Question

Query ICS external adapter on Windows 10 or 11

Hao Zhuang 1

I need to programmatically find the external (Internet) adapter (network interface), either GUID, LUID or InterfaceIndex, used for Internet Connection Sharing service. There is a reg value entry under HKLM\System\CCS\Services\icssvc\Settings of the "PreferredPublicInterface". But I'm afraid it is not the right way to do it. Could you please advise what APIs can be used to retrieve this information on Windows 10 or 11?

Thanks in advance!

Castorix31 90,686 Reputation points

2022-01-21T13:18:53.933+00:00

If you mean this How to Enable or Disable Internet Connection Sharing (ICS) in Windows,
I get it from some ICS COM interfaces on Windows 10
Hao Zhuang 1 Reputation point

2022-02-16T00:53:38.267+00:00

Sorry but no that's not what I'm asking. I wish to find out which connection/adapter/network-interface ICS is using as the Internet connection (a.k.a., public, or external, etc.), exactly as the title of this question states.

2 answers

Your answer

Castorix31 90,686 Reputation points

2022-01-21T13:18:53.933+00:00

If you mean this How to Enable or Disable Internet Connection Sharing (ICS) in Windows,
I get it from some ICS COM interfaces on Windows 10
Hao Zhuang 1 Reputation point

2022-02-16T00:53:38.267+00:00

Sorry but no that's not what I'm asking. I wish to find out which connection/adapter/network-interface ICS is using as the Internet connection (a.k.a., public, or external, etc.), exactly as the title of this question states.

Answer 1

Xiaopo Yang - MSFT 12,731 Microsoft External Staff

Hello,

Welcome to Microsoft Q&A!

the GetAdaptersAddresses and GetInterfaceInfo functions can retrieve all adapters information on the local computer. But I don’t know the PreferredPublicInterface meaning.

Thank you.

If the answer is the right solution, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.

Hao Zhuang 1 Reputation point

2022-01-20T19:53:01.873+00:00

Thanks for the reply but this is not what I'm looking for. Already know what IP Helper API can do. I just need to find out the Network Interface that ICS uses as the Internet connection ("public"). ICS is the Microsoft's NAT service comes with Windows since, maybe, Windows 2000.

Win 10/11 has some network APIs via UWP such as Windows.Networking.Connectivity.NetworkInformation.GetInternetConnectionProfile(), NetworkOperatorTetheringManager, etc. However, none of them seem to pinpoint the "public" interface used by ICS. GetInternetConnectionProfile() usually returns the same interface as ICS "public". But not always.
Xiaopo Yang - MSFT 12,731 Reputation points Microsoft External Staff

2022-01-21T01:59:19.533+00:00

I found the Internet Connection Sharing (ICS) API. You can use INetSharingManager::get_EnumEveryConnection to retrieve an enumeration interface for all connections in the connections folder. Do not forget to see the documentation on About Internet Connection Sharing and Internet Connection Firewall. A quick search example.
Hao Zhuang 1 Reputation point

2022-01-21T02:25:00.013+00:00

Unfortunately I don't believe this COM interface still works in Win 10/11.
Xiaopo Yang - MSFT 12,731 Reputation points Microsoft External Staff

2022-01-21T03:10:58.04+00:00

Or As the document suggests, use the Windows Firewall API.
Hao Zhuang 1 Reputation point

2022-01-21T06:27:26.22+00:00

I didn't find anything related to ICS. Please give a specific pointer which API to use if there is any info from the MSFT team.
Castorix31 90,686 Reputation points

2022-01-21T12:07:00.717+00:00

I don't believe this COM interface still works in Win 10/11.

Just test them and you will see they work at least on Windows 10
(I tested successfully INetSharingManager on Windows 10 21H1)
Xiaopo Yang - MSFT 12,731 Reputation points Microsoft External Staff

2022-02-15T09:49:54.37+00:00

I don't believe this COM interface still works in Win 10/11.

I tested and Internet Connection Sharing (ICS) API works on Windows11.
Hao Zhuang 1 Reputation point

2022-02-15T21:29:51.75+00:00

Did you try enabling ICS by Settings -> Network & Internet -> Mobile hotspot? When you enable your PC as "Mobile hotspot" ICS is started to perform NAT. But with that COM interface get_EnumPublicConnections() fails and get_EnumEveryConnection() doesn't return the public connection as "Shared".

And "Mobile hotspot" is preferred/most common way to start ICS in Windows 10/11.
Xiaopo Yang - MSFT 12,731 Reputation points Microsoft External Staff

2022-02-16T02:55:45.243+00:00

Is Shared important? When you retrieve the connections, you can get the adapter information. Also Try the Microsoft ICS Sample.
Finally, I suppose the Services\icssvc\Settings works.
Hao Zhuang 1 Reputation point

2022-02-16T06:48:43.66+00:00

Yes, it is important and is exactly what I'm asking for. The ICS API just doesn't work well in the Mobile hotspot scenario. Since you are from Microsoft, if you could contact the dev owner of ICS and get a definitive answer from the team that will be greatly appreciated!

Thanks !

Answer 2

Limitless Technology 39,931

Hello HaoZhuang

You can use WMI instance to retrieve the information, for example:

Get-CimInstance -Class CIM_NetworkAdapter -ComputerName localhost -ErrorAction Stop | Select-Object *

This will show you all the properties, then you can select the one you want.

--If the reply is helpful, please Upvote and Accept as answer--

Hao Zhuang 1 Reputation point

2022-01-23T06:48:32.15+00:00

I don't find the info I need. Could you please enlighten me which property of the output should I look into??

Share via

Query ICS external adapter on Windows 10 or 11

2 answers

Your answer