Turn off Wi-Fi on your Mac.
Open Finder and press Command-Shift-G.
Paste this location and Go: /Library/Preferences/SystemConfiguration
Move these files to Trash:
com.apple.airport.preferences.plist
com.apple.network.eapolclient.configuration.plist
com.apple.wifi.message-tracer.plist
NetworkInterfaces.plist
preferences.plist
Restart Mac.