How can I reset all preferences in VirtualBox?
Basta excluir o diretório ".VirtualBox" oculto em seu diretório de perfil de usuário (que é referido como $ Home na citação abaixo do manual on-line do VirtualBox.
In addition to the files of the virtual machines, VirtualBox maintains global configuration data. On Linux and Solaris as of VirtualBox 4.3, this is in the hidden directory $HOME/.config/VirtualBox, although $HOME/.VirtualBox will be used if it exists for compatibility with earlier versions; on Windows (and on Linux and Solaris with VirtualBox 4.2 and earlier) this is in $HOME/.VirtualBox; on a Mac it resides in $HOME/Library/VirtualBox.
VirtualBox creates this configuration directory automatically if necessary. Optionally, you can supply an alternate configuration directory by setting the VBOX_USER_HOME environment variable, or additionally on Linux or Solaris by using the standard XDG_CONFIG_HOME variable. (Since the global VirtualBox.xml settings file points to all other configuration files, this allows for switching between several VirtualBox configurations entirely.)
Most importantly, in this directory, VirtualBox stores its global settings file, another XML file called VirtualBox.xml. This includes global configuration options and the list of registered virtual machines with pointers to their XML settings files. (Neither the location of this file nor its directory has changed with VirtualBox 4.0.)
Além disso,
