Error Firewall IPNat.sys

Masalah ini terjadi ketika Server tidak bisa diakses oleh Computer lain, padahal melalui Server tersebut akses ke ip terdapat folder-folder yang disharing. Dan computer lain tidak bisa melakukan ping ke server.
Solusinya :
1. Klik kanan My Computer>Manager>Services and Applications>Services.
2. Disable Routing and Remote Access service
3. Setting ulang Gateway pada TCP/IP
4. Jika diperlukan lakukan "Repair"
5. Masuk CMD dan jalankan perintah "ipconfig /flushdns"
Beres deh.

Found this tidbit while researching this problem:
Can't enable windows Firewall on a RRAS server - Windows firewall cannot run because another program or service is running that might use the network address translation component (Ipnat.sys)
Situation: one of our clients could not get the windows Firewall to work. Whenever they tried to start the Windows Firewall, they received the following message: "Windows firewall cannot run because another program or service is running that might use the network address translation component (Ipnat.sys).

What they tried:

They event tried to stop the RRAS but got the same result. They finally make it work by disabling the RRAS.

Recommendation: It is not recommended to use Windows Firewall on a RRAS server. If you use the server as a router, you should enable NAT; if you use the server as VPN, you should have another firewall. If, for some reasons, you do want to enable Windows Firewall in the Windows 2003, you may need to disable the RRAS. To do that, right-click on My Computer>Manager>Services and Applications>Services. Disable Routing and Remote Access service

When I disabled RRAS, I could get into my Firewall settings. I then shut off my firewall and re-configured RRAS.

Sukses bro...