As long as both machines are getting different and valid IP addresses from the network this should work. However make sure you have the VirtualBox Guest Additions installed. If not I would look at:
I would assume you can successfully ping the host from the guest and the other way around.
The other option is to use Shared Folders, which allows you to access host directly.
Also check that you have bound the Virtual Machine to the correct network card. This is relevant especially when you have Wireless.
- Virtual Machine Settings
- Network
- Adapter 1 (Select the one you are using)
- Adapter Type: (Leave as is)
- Attached to: Bridged Adapter
- Name: (Select the correct physical card here)
Also make sure the information box is not giving a big red error at this point.