DHCP works but no internet

[avibodha]

Hi, I have CentOS 6 virtualbox running as a guest on Win7 host using the Bridged adapter. Have DHCP set up and can see that Centos obtained a good ip, has the gateway set right, has correct dns servers. But I can't ping google etc. It has worked until recently, installed/uninstalled some programs.

What would keep the network from working once it has obtained a valid DHCP address etc?
When I view network adapter properties, there are only known good items. Virtualbox Bridged network filter is on. Also, ping to gateway fails (10.0.0.1). Tried changing VB network adapter, no change.

Have uninstalled-reboot-installed Virtualbox, same situation. Rebooted Centos, checked network settings. Reinstalled Guest Additions, no change.

Update:
Set up additional network adapter (eth1) and this works! So, there is a problem with eth0 for some reason, but it gets DHCP info fine, but can't ping gateway address it gets.
Disabled first network adapter, and only adapter 2 (previously eth1) and now it as eth0 doesn't work. So perhaps eth0 is corrupted somehow?

Any ideas on where to turn next?

[noteirak]

From the description you give here, the problem has nothing with Virtualbox. the TCP/IP stack is up and running, there is an issue with the "outside".
You should seek support on a networking forum first, as everything points to a network (re)configuration problem.

[avibodha]

thanks, yes, I found the problem was with a router. Had a reserved ip set up but somehow router was just not responding to this ip. deleted reserved ip and re-entered and now works fine.