Qt WARNING: VirtualBox: cannot connect to X server

Oracle VM VirtualBox Manager 5.0.18 (C) 2005-2016 Oracle Corporation All rights reserved. Usage: --startvm <vmname|UUID> start a VM by specifying its UUID or name --separate start a separate VM process --normal keep normal (windowed) mode during startup --fullscreen switch to fullscreen mode during startup --seamless switch to seamless mode during startup --scale switch to scale mode during startup --no-startvm-errormsgbox do not show a message box for VM start errors --restore-current restore the current snapshot before starting --no-aggressive-caching delays caching media info in VM processes --fda <image|none> Mount the specified floppy image --dvd <image|none> Mount the specified DVD image --dbg enable the GUI debug menu --debug like --dbg and show debug windows at VM startup --debug-command-line like --dbg and show command line window at VM startup --debug-statistics like --dbg and show statistics window at VM startup --no-debug disable the GUI debug menu and debug windows --start-paused start the VM in the paused state --start-running start the VM running (for overriding --debug*) Expert options: --disable-patm disable code patching (ignored by AMD-V/VT-x) --disable-csam disable code scanning (ignored by AMD-V/VT-x) --recompile-supervisor recompiled execution of supervisor code (*) --recompile-user recompiled execution of user code (*) --recompile-all recompiled execution of all code, with disabled code patching and scanning --execute-all-in-iem For debugging the interpreted execution mode. --warp-pct <pct> time warp factor, 100% (= 1.0) = normal speed (*) For AMD-V/VT-x setups the effect is --recompile-all. The following environment (and extra data) variables are evaluated: VBOX_GUI_DBG_ENABLED (GUI/Dbg/Enabled) enable the GUI debug menu if set VBOX_GUI_DBG_AUTO_SHOW (GUI/Dbg/AutoShow) show debug windows at VM startup VBOX_GUI_NO_DEBUGGER disable the GUI debug menu and debug windows