Guest Windows 2012: Internet OK with NAT but not with Bridge

[AntiMatter]

Hi,

This is not a Virtualbox issue. But I hope you can help.

Using VirtualBox 4.20 on Host LinuxMint 11 x64. I created a new VM and installed Windows Server 2012 standard. Then I installed Guest Addtions and made some simple settings like changing Computer name. Windows network settings are all default. The VM cannot access the Internet if the VM Network Settings is Bridged Adapter. As soon as I changed to NAT, the VM could access Internet. Weirder yet, I also installed the same Windows Server 2012 on a physical machine. And here too, Windows cannot access Internet either.

All other devices in the subnet could access Internet OK. Router has been rebooted and the router log show that it captured the outgoing request from Windows 2012 (for example http to google.com).

Do you have any idea as why Windows 2012 guest reacts differently between NAT (internet works) and Bridged (no internet)? Could that be the router?

Thanks in advance for any help.

[AntiMatter]

FIXED: It's the router, I changed for a new one and the issue is gone.