VirtualBox - Error E_FAIL ProgressProxy

On a dual boot system (Windows XP + Linux Mint 15) I got an error named E_FAIL in component ProgressProxy.

The reason was that the path to the .vdi file in the .vbox config file was invalid.

The config on Windows XP was located at:

C:\Documents and Settings\<Username>\VirtualBox VMs\<VirtualBox name>\<VirtualBox name>.vdi

Opened it in Notepad++ and edited the invalid HardDisk line/tag there, now I did not get any errors, but the virtual machine freezes on boot.