SetInterfaceDnsSettings function (netioapi.h) does not work?

Question

I want to change the DNS of a network adapter with C++

I came across this SetInterfaceDnsSettings function https://learn.microsoft.com/en-us/windows/win32/api/netioapi/nf-netioapi-setinterfacednssettings

This is my code.

The ret value returned is 0, so I guess it means no error. But the DNS setting of the interface did not change.

The interface guid is got from GetAdaptersInfo() function.

GUID interfaceGUID;
    LPCOLESTR lpsz = L"{1CA18531-B5FA-4A92-837A-AE12298FFF7F}";
    HRESULT hr = CLSIDFromString(lpsz, &interfaceGUID);
    if (hr != S_OK)
    {
        printf("get guid error!!!\n");
        exit(1);
    }

    DNS_INTERFACE_SETTINGS settings = {DNS_INTERFACE_SETTINGS_VERSION1, 0, NULL, L"8.8.8.8", NULL, 0, 0, 0, 0, NULL};
    printf("NameServer         : %ls\n", settings.NameServer);

    DWORD ret = SetInterfaceDnsSettings(interfaceGUID, &settings);
    printf("result: %lu\n", ret);

Answer 1

Try to specify DNS_INTERFACE_SETTINGS.Flags with DNS_SETTING_NAMESERVER.