[SOLVED] VirtualBox Could not read from the boot medium

I have an Ubuntu 14.04 physical server which I am attempting to virtualize.

Following are the steps I have followed.
- Create an image of the drive. dd if=/dev/sdb of=server.raw bs=1024
- Create a VDI using VBoxManage. VBoxManage convertdd server.raw TestServer.vdi --format VDI --variant Fixed
- Created a virtual machine using TestServer.vdi as the disk.

When I attempt to boot the virtual machine, I receive a message stating, "FATAL: Could not read from the boot medium! System halted."

I started the VM using an Ubuntu CD and checked the partitions. They match the physical system exactly and the fstab on the virtual system matches the physical system exactly.

UUIDs are used in fstab and they match on the physical and virtual systems.

Any suggestions as to why the VM will not boot would be greatly appreciated.

Thank you!