You have to access the modem/built in router, and turn on WPA. You then set the PCs to the same code key you set in the modem/router. Since you gave no modem make, model, or OS this is as far as I can go.
hi,
I HAVE A WIRELESS MODEM AND I USE IT TO CONNECT BOTH MY LAPTOP AND DESKTOP TO THE INTERNET.HOW DO I PASSWORD PROTECT IT?BECAUSE MY NEIGHBOUR'S GET THE SIGNAL TOO AND I WANNA SECURE THE NETWORK.

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