In Hyper-V Manager, select Virtual Switch Manager… from the ‘Actions’ menu on the right.

Under the ‘Virtual Switches’ section, select New virtual network switch.
Under ‘What type of virtual switch do you want to create?’, select Internal.
Select the Create Virtual Switch button.

Under ‘Virtual Switch Properties’, give the new switch a name such as Internal.
Select Apply to create the virtual switch. At this point you will most likely see the following message. Click Yes to continue.
Select OK to close the Virtual Switch Manager Window.

Repeat the same steps to create External Virtual Switch
