Reset DNS Servers on Mac

Step-by-Step

1. Click on the Apple logo  in the top left of the screen and select System Preferences.
2. Click on Network.
3. In the left hand navigation column, click the first connection that is marked Connected to select it. All active connections have a green dot next to them.
4. Click the Advanced button found in the lower right corner.
5. Click the DNS tab. In the left hand list for DNS servers, select all entries one by one and click the – (minus) button to remove it from the list until the list is empty.
6. Once no manual entries exist on the list, it will show the default DNS servers given to the machine via DHCP.

Repeat steps 5 and 6 for all active connections.