On Linux, Oracle VM VirtualBox makes use of a custom version of Mozilla XPCOM (cross platform component object model) for interprocess and intraprocess communication (IPC). The process VBoxSVC serves as a communication hub between different Oracle VM VirtualBox processes and maintains the global configuration, such as the XML database. When starting an Oracle VM VirtualBox component, the processes VBoxSVC and VBoxXPCOMIPCD are started automatically. They are only accessible from the user account they are running under. VBoxSVC owns the Oracle VM VirtualBox configuration database which normally resides in ~/.config/VirtualBox, or the appropriate configuration directory for your operating system. While it is running, the configuration files are locked. Communication between the various Oracle VM VirtualBox components and VBoxSVC is performed through a local domain socket residing in /tmp/.vbox-username-ipc. In case there are communication problems, such as an Oracle VM VirtualBox application cannot communicate with VBoxSVC, terminate the daemons and remove the local domain socket directory.