- Hit Winkey + R to open Run prompt and type gpedit.msc
- Navigate to:
Computer Configuration/Windows Settings/Security Setting /Network List Manager Policies
.
- Choose your Network name in the right pane.
Note: To show networks not currently connected, right-click Network List Manager Policies in the left pane and choose Show All Networks.
- Go to Network Location tab and change the Location type from Public to Private.
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- Close Local Policy Editor.
Source: https://social.technet.microsoft.com/Forums/lync/en-US/82ccc68c-947e-435a-a237-1090f38d0dbe/windows-server-2012-r2-datacenter-network-stuck-in-public-mode