Issue: Undefined variable: installurl

ErrorException: Undefined variable: installurl - vault/core/controller/cp/vw.php:174 
Generated By: alfa, A moment ago

Stack Trace
#0 /vault/core/controller/cp/vw.php(174): XenForo_Application::handlePhpError(8, 'Undefined varia...', '/home/...', 174, Array)
#1 /library/vw/XenForo/ControllerAdmin/Wiki.php(131): vw_CP_Controller->install_safety_check()
#2 /library/vw/XenForo/ControllerAdmin/Wiki.php(114): vw_XenForo_ControllerAdmin_Wiki->assert_permission(Object(vw_CP_Index_Controller))
#3 /library/XenForo/FrontController.php(351): vw_XenForo_ControllerAdmin_Wiki->actionIndex()
#4 /library/XenForo/FrontController.php(134): XenForo_FrontController->dispatch(Object(XenForo_RouteMatch))
#5 /admin.php(13): XenForo_FrontController->run()
#6 {main}
Request State
array(3) {
  ["url"] => string(53) "/admin.php?wiki/"
  ["_GET"] => array(1) {
    ["wiki/"] => string(0) ""
  }
  ["_POST"] => array(0) {
  }
}