Disabling IPv6 in Windows has solved many issues for users, but, in all fairness, it's also caused a few. If you're sure you need to disable IPv6 in Windows 10, here's how.
Editing the properties of a network adapter and unchecking the IPv6 checkbox only unbinds IPv6 from that particular network adapter. It doesn't disable IPv6 in Windows and it doesn't solve the common problems with IPv6 in Windows. To cleanly disable IPv6 a registry key must be added.
Beware, messing up the Windows registry can ruin your Windows install. Tread lightly and be careful.
Like just about everything else in Windows, there's at least two ways to add this registry key. If your comfortable using the command prompt, you can use the Command Prompt Method near the bottom of this post.
Sign into Windows 10 with an account that has local admin privileges.
Click on the Start button, type regedit, and press the enter key.
Click the Yes button when prompted by UAC.
Use Registry Editor to expand the registry tree and browse to:
Right click on Parameters, expand New, and select DWORD (32-bit) Value.
Enter DisabledComponents into the Name field.
Right click on the new DisabledComponents value and select Modify.
Enter ffffffff into the Value data dialog box, and click the OK button.
Confirm the new registry value contains the required data.
Restart the computer and IPv6 will be disabled
Verify that IPv6 is disabled by running ipconfig /all from the command prompt. The output should only show IPv4 addresses and no 6to4 adapters.
IPv6 can be enabled by either deleting the DisabledComponents registry value or changing its data to 0.
Command Prompt Method
Adding a registry key with the command prompt can be easier for some people and more dangerous for others.
Start a command prompt with administrative permissions and enter (or copy and paste) the following command and press the Enter key:
reg add hklm\system\currentcontrolset\services\tcpip6\parameters /v DisabledComponents /t REG_DWORD /d 0xFFFFFFFF
Restart the computer and IPv6 will be disabled.