How to Disable IPv6 on MacOS and Windows (Network)

Objective

Following these steps will disable IPv6 on your device.

Environment

Windows 7 and higher
MacOS 10.5 (Leopard) and higher

Before You Begin

If your computer was previously successfully registered on the DHCP registration page and has begun denying further access to the network by looping back to the DHCP registration page, follow the steps below to disable IPv6 on your computer. In many cases this will resolve the issue. 

Steps

Windows:

1. Open Start > Settings
2. Select Network and Internet
3. Select Change Adapter Options
4. Right-click your connection from the list and choose Properties
5. Uncheck the box next to Internet Protocol Version 6 (TCP/IPv6)
6. Select OK
7. Flush your DNS data
   1. Type cmd in the search box by the Start Menu
   2. Type ipconfig /flushdns in the command window that opens
8. Restart your machine
9. You're done! IPv6 should now be disabled for your connection on your device.

MacOS:

1. Open the Apple menu and select System Preferences
2. Select Network
3. Select Ethernet
4. Select Advanced and then select the TCP/IP tab and make the following changes/confirm settings
   1. Configure IPv4: set to Automatically or Using DHCP
   2. Configure IPv6: set to Link Local Only or Off
5. Select OK
6. Select Apply
7. Restart your device.
8. You're done! IPv6 should now be disabled for your connection on your device.

Additional Info

DNS Flooding / Blocked user

If your computer begins acting as a rogue domain name server (DNS) due to IPv6 settings (typically under Vista), it may result in DNS flooding that affects many other users. Upon identification, a problem computer will be blocked from network access until the settings are corrected.

If your machine is blocked, you will be sent an email informing you that your computer is "flooding the network" and has been blocked from access.