How to Reinstall Isatap
The Microsoft Inter Site Automatic Tunneling Address Protocol, or ISATAP, device is responsible for allowing the newer IPv6 protocol to work inside the older IPv4 protocols. This is beneficial for network infrastructures that are working to merge their system over to the newer protocol. This device allows users to start creating software that utilizes IPv6 packets while also allowing systems on an IPv4 network to communicate within the application's inbound and outbound traffic. Without this device driver, these networks would be forced to use only one version. If you suspect a problem with the ISATAP device driver, you can reinstall it through the Windows Device Manager component.
Press the "Windows" and "R" keys simultaneously. This displays a "Run" dialog box.
Type "Devmgmt.msc" in the dialog box and click "OK."
Click "View" and click "Show Hidden Devices."
Double-click "Network" adapters. This expands a list of all network devices installed.
Right-click "Microsoft ISATAP" and click "Uninstall." Click "OK" on the confirmation dialog box. This automatically removes the adapter.
Click "Action" and select "Add Legacy Hardware." This opens a Welcome to the Add Hardware Wizard dialog box.
Click "Next." This brings you to two options.
Click the "Install the hardware that I manually select from a list (Advanced)" option and click "Next." This loads a list of hardware types in a new window.
Double-click "Network adapters" from the list of hardware types. This will display a list of network device manufacturers in the left pane.
Double-click "Microsoft" from the manufacturer list in the left pane. This displays all Microsoft-related devices in the right pane.
Double-click "Microsoft ISATAP Adapter" in the right pane and click "Next" to install it.
Click "Finish" on the Device Installation Complete dialog box and restart your computer.