diff --git a/js/ui/windowManager.js b/js/ui/windowManager.js
index 17576a07e..d6bfe6ac1 100644
--- a/js/ui/windowManager.js
+++ b/js/ui/windowManager.js
@@ -1173,6 +1173,10 @@ var WindowManager = new Lang.Class({
                 yScale = geom.height / actor.height;
             } else {
                 let monitor = Main.layoutManager.monitors[actor.meta_window.get_monitor()];
+                if (!monitor) {
+                    this._minimizeWindowDone();
+                    return;
+                }
                 xDest = monitor.x;
                 yDest = monitor.y;
                 if (Clutter.get_default_text_direction() == Clutter.TextDirection.RTL)
@@ -1248,6 +1252,11 @@ var WindowManager = new Lang.Class({
                                 geom.height / actor.height);
             } else {
                 let monitor = Main.layoutManager.monitors[actor.meta_window.get_monitor()];
+                if (!monitor) {
+                    actor.show();
+                    this._unminimizeWindowDone();
+                    return;
+                }
                 actor.set_position(monitor.x, monitor.y);
                 if (Clutter.get_default_text_direction() == Clutter.TextDirection.RTL)
                     actor.x += monitor.width;