virtualbox.org

You have two choices.

• 1) boot in recovery mode and fix the guest.
  2) install again and make sure you install properly.

I can not give you any more information than that because it involves too many options on proper installation of the Linux guest. All I can say at this point it must be an issue with your install since VirtualBox does not see any problems.

If you select all of the default values in the guest when installing it should boot up. There is one exception. When installing grub it asks if you want to manually install grub of install it to the entire disk. You should always select to install it to the entire disk if you do not understand how to manually install grub.