Apologies for the English! My KPN box 12b is running software version: V12.c.23.04.39 and I’ve been trying to change the DNS server my router uses, but the option to change the server is greyed out.
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A different post had a solution that consisted of unticking some box, but that box is not available anywhere as far as I can tell. How can I alter the DNS server of my router, and ideally also set up a secondary DNS server address?