Windows 7, 8 and 10 have a "feature" that can really catch you out. Windows always assumes that networks that you connect to for the first time are "public" networks. They do this so that you will be protected by default by having network and sharing services turned off for new networks. Its a good idea when you are out and about with your laptop but sometimes it can catch you out. For example replace your router and you may or may not notice that some of the expected Windows ftionality stops working because Windows has detected that you are now connected to a "new" network.

See the steps below to change the currently connected network to be accepted as private (i.e. safe) on each PC on your network.

[Screen shots are from Windows 10 but other versions are almost identical]

Click on Windows file explorer (see 1 below)

Click on "network" (see 2 below) and if you see the message showing at 3 (below) then your PC is not detecting the current network as a private network i.e. not secure.

Click on the message and chose "Turn on network discovery and file sharing" (See 4 below)

You will then be prompted to chose to make the current network private (and as such considered safe) (see 5 below) or turn on sharing and discovery for all public networks (including the currently connected assumed "insecure public" network) (see 6 below). The safer choice and the one to always use on a laptop or mobile computer is the top one (see 5 below)

Once you have made the selection you should begin to see your other network devices and other devices on the network will be able to see you depending on their permissions to do so. (see 6 below)

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