While I can deduce PPPoE, CPE here means Customer-premises equipment so I can't guess what's up here.
Whatever this CPE is, my bet is you'll be talking to it's maker.
Hello,
I am connecting CPE(client router) to sector antennas. If I create PPPOE connection in CPE, it works fine but if I am creating PPPOE connection on laptop it doesnt work and gives the error 651.
What might be the issue?

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