Go back to "Network and Sharing," select "Advanced Sharing Settings," and scroll down to "Password Protected Sharing."

, Select your new password, and distribute this new password to your family or coworkers that are in your network.
 This can help you to make sure that all of your settings are set to protected status. This includes file and printer sharing, HomeGroup or WorkGroup connections, public folder sharing, and file sharing connections.
Create a network security key if there isn't one already available.
Select the option to "Turn on Password Protected Sharing.",
Change all other settings within the "Advanced Sharing Settings" page.
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