I have just upgraded to Windows 8.1, and after the upgrade process is finished, I can't connect to internet.

I tried running the "Troubleshoot problems":

It concluded that DHCP needs to be activated:

I let it activate DHCP, and I got internet connection back.

The problem is I want to set this PC to a certain IP address (the IP address that it has been using all this time).

I am also using Hyper-V, which I suspect has something to do with this problem.

After I regained internet connection, I tried running one of my Hyper-V VM. From inside the VM I can connect to internet. That VM has static IP address.

I also noticed that in "Control Panel\Network and Internet\Network Connections", I usually have a network connection called vEthernet (Realtek PCIe GBE Family Controller Virtual Switch). I didn't find it there after upgrade.

How do I set my PC to a static IP while retaining internet access in Windows 8.1?

EDIT

I have managed to recreate vEthernet (Realtek PCIe GBE Family Controller Virtual Switch) by unchecking Allow management operating system to share this network adapter in Hyper-V's Virtual Switch Manager and then checking it again.

But when I changed the adapter to use static IP, it still can't connect to internet.

Result of Get-NetAdapter -Name * | fl (with MAC address removed):

Name                       : vEthernet (Realtek PCIe GBE Family Controller Virtual Switch)
InterfaceDescription       : Hyper-V Virtual Ethernet Adapter #2
InterfaceIndex             : 5
MacAddress                 : 55-55-55-55-55-55
MediaType                  : 802.3
PhysicalMediaType          : Unspecified
InterfaceOperationalStatus : Up
AdminStatus                : Up
LinkSpeed(Mbps)            : 100
MediaConnectionState       : Connected
ConnectorPresent           : False
DriverInformation          : Driver Date 2006-06-21 Version 6.3.9600.16384 NDIS 6.40

Name                       : Ethernet 3
InterfaceDescription       : Hyper-V Virtual Ethernet Adapter #3
InterfaceIndex             : 6
MacAddress                 : 55-55-55-55-55-56
MediaType                  : 802.3
PhysicalMediaType          : Unspecified
InterfaceOperationalStatus : Up
AdminStatus                : Up
LinkSpeed(Gbps)            : 10
MediaConnectionState       : Connected
ConnectorPresent           : False
DriverInformation          : Driver Date 2006-06-21 Version 6.3.9600.16384 NDIS 6.40

Name                       : Ethernet
InterfaceDescription       : Realtek PCIe GBE Family Controller
InterfaceIndex             : 2
MacAddress                 : 55-55-55-55-55-57
MediaType                  : 802.3
PhysicalMediaType          : 802.3
InterfaceOperationalStatus : Up
AdminStatus                : Up
LinkSpeed(Mbps)            : 100
MediaConnectionState       : Connected
ConnectorPresent           : True
DriverInformation          : Driver Date 2013-05-10 Version 8.1.510.2013 NDIS 6.30