diff --git a/OpenRA.Game/Widgets/ProgressBarWidget.cs b/OpenRA.Game/Widgets/ProgressBarWidget.cs
index f2fb407776..ed462c5ef6 100644
--- a/OpenRA.Game/Widgets/ProgressBarWidget.cs
+++ b/OpenRA.Game/Widgets/ProgressBarWidget.cs
@@ -18,6 +18,8 @@ namespace OpenRA.Widgets
 	public class ProgressBarWidget : Widget
 	{
 		public int Percentage = 0;
+		public bool Indeterminate = false;
+		int indeterminateTick = 0;
 		
 		public ProgressBarWidget() : base() {}
 		protected ProgressBarWidget(ProgressBarWidget widget)
@@ -29,12 +31,20 @@ namespace OpenRA.Widgets
 		public override void DrawInner()
 		{
 			WidgetUtils.DrawPanel("dialog3", RenderBounds);
+			Rectangle barRect = Indeterminate ? 
+				new Rectangle(RenderBounds.X + 2  + (int)((RenderBounds.Width - 4)*(-Math.Cos(Math.PI*2*indeterminateTick/100) + 1)*3/8), RenderBounds.Y + 2, (RenderBounds.Width - 4) / 4, RenderBounds.Height - 4) : 
+				new Rectangle(RenderBounds.X + 2, RenderBounds.Y + 2, Percentage * (RenderBounds.Width - 4) / 100, RenderBounds.Height - 4);
 			
-			var barRect = new Rectangle(RenderBounds.X + 2, RenderBounds.Y + 2, Percentage * (RenderBounds.Width - 4) / 100, RenderBounds.Height - 4);
 			if (barRect.Width > 0)
 				WidgetUtils.DrawPanel("dialog2", barRect);
 		}
 		
+		public override void Tick()
+		{
+			if (Indeterminate && indeterminateTick++ >= 100)
+				indeterminateTick = 0;
+		}
+		
 		public override Widget Clone() { return new ProgressBarWidget(this); }
 	}
 }
\ No newline at end of file
diff --git a/OpenRA.Mods.RA/Widgets/Delegates/GameInitDelegate.cs b/OpenRA.Mods.RA/Widgets/Delegates/GameInitDelegate.cs
index 66efbf69e0..06cdfc4f12 100755
--- a/OpenRA.Mods.RA/Widgets/Delegates/GameInitDelegate.cs
+++ b/OpenRA.Mods.RA/Widgets/Delegates/GameInitDelegate.cs
@@ -90,12 +90,12 @@ namespace OpenRA.Mods.RA.Widgets.Delegates
 			window = Widget.OpenWindow("INIT_COPY");
 			var status = window.GetWidget<LabelWidget>("STATUS");
 			var progress = window.GetWidget<ProgressBarWidget>("PROGRESS");
-			
+			progress.Indeterminate = true;
+
 			// TODO: Handle cancelling copy
-			// TODO: Make the progress bar indeterminate
+			window.GetWidget<ButtonWidget>("CANCEL").IsVisible = () => false;
 			window.GetWidget("CANCEL").OnMouseUp = mi => { ShowInstallMethodDialog(); return true; };
 			window.GetWidget("RETRY").OnMouseUp = mi => PromptForCD();
-			window.GetWidget<ButtonWidget>("CANCEL").IsVisible = () => false;
 
 			status.GetText = () => "Copying...";
 			var error = false;
@@ -144,6 +144,7 @@ namespace OpenRA.Mods.RA.Widgets.Delegates
 				{
 					// Automatically extract
 					status.GetText = () => "Extracting...";
+					progress.Indeterminate = true;
 					var error = false;
 					Action<string> parseOutput = s => 
 				    {