I recently can’t access the internet with Virtual Box, so I checked Windows Device Manager in Windows 7. I saw a yellow exclamation mark for Virtualbox Host-Only Ethernet Adapter. Apparently, the device driver was corrupted or missing. I tried removing it by right clicking Virtualbox Host-Only Ethernet Adapter and picking uninstall, but Windows won’t let me. I can only disable it. But, disabling Virtualbox Host-Only Ethernet Adapter won’t do me any good since I still can’t go online if Virtual box network adapter is disable. I notice I also had a similar problem with VMware player, but I can just do a repair install of VMware player to fix its networking problem. I think when I did a repair install of Windows 7. Windows 7 could not find the driver software for my virtual machine players.
1. You need to open Device manager. In Windows 7, just type “device manager” in the Windows Start Menu search text box. (skip this step if you have device manager already open)
2. Double click on Virtualbox Host-Only Ethernet Adapter in device manager.
3. Go to Drivers tab, and click update drivers button.
4. Click the “Browse my computer for driver” option.
5. Browse to the location you installed Virtual Box to. It is usually C:\program files\sun\virtualbox for most users. Click the Next button.
If everything goes well, you should be done. If your driver installation is unsuccessful. You should uninstall VirtualBox, and Reinstall Virtual box, and repeat steps 1-4 again.
This method of manually installing driver software also works for other programs, and hardware like video cards, etc.