How to enable NAT on Windows 7...

I am not able to use netsh routing commands on WIndows 7. These commands work on Windows XP. Upon research I found that Windows 7 does not support routing commands. On Vista there was workaround by using "netsh add helper ipmontr.dll" and "netsh add helper ippromon.dll" but these commands does not work on Windows 7.

Can anyone help me to setup NAT on Windows 7. One more question, if NAT is disabled on WIndows 7, How does VirtualBox use NAT for guest PC to communicate with Host PC network machines.

Thanks
Chandra

So are you saying I cannot enable NAT on Windows 7 but should install Windows Server 2008 R2 to have NAT. If so, then how is VirtualBox working.

Also what do you mean router. How can I install virtual router without using NAT.

Thanks
Chandra

My requirement

Say, Machine1 is in network N1, Machine2 is in network N1 and N2. Machine3, Machine4 is in network N2

In the above setup Machine1 should be able to talk to both Machine3 and Machine4 via Machine2. In XP we used to achieve this by using NAT routing and port forwarding. Any communication to port P1 on Machine2 from network N1 will be forwarded to Machine3. Any communication to port P2 on Machine2 from network N1 will be forwarded to Machine4. So any time any machine from N1 talks to Machine2:P1, the data is forwarded to Machine3, any data to Machine2:P2 will be forwarded to Machine4.

How to achieve this in Windows 7

hi ....... you can use GNS cisco and add the router you want ..... then you will have nat on your windows 7