DNS ( Domain Name System), is a local directory that every computer keeps for internet addresses. The addresses dictate how long the computer should store the current address for, before checking for updates on this address.
Occasionally the local computer stores this address longer then it should and this can result it to pointing to an address that no longer exists.
Use the steps below to clear/reset the current Mac OS directory, forcing it to get the latest updates.
- Run the terminal.app using your preferred method. You can launch the app from Applications -> Utilities or press Command + Space to launch Spotlight and search for Terminal.
- Type in
sudo killall -HUP mDNSResponderand hit Return on your keyboard.
- Enter the administrator password for the account in question and hit Return
Thats it. This should clear your local directory.
If you are unsure about following the above steps, you can try restarting the Mac completely first. This can also help.