Internet naming service file
INS is a system file used by Windows Internet Naming Service (WINS). INS files hold information collected by the NetBIOS name resolution service. INS files hold IP addresses and names assigned to them by WINS. This information is needed for network services that use operating systems or applications that rely on NetBIOS. INS files are not meant to be manually opened or edited.
Learn more about .INS files:
Chris Partsenidis explains the difference between DNS and WINS.
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