diff --git a/src/net/azib/ipscan/gui/AbstractModalDialog.java b/src/net/azib/ipscan/gui/AbstractModalDialog.java
index 592642d5..46bba7f3 100755
--- a/src/net/azib/ipscan/gui/AbstractModalDialog.java
+++ b/src/net/azib/ipscan/gui/AbstractModalDialog.java
@@ -46,13 +46,12 @@ public abstract class AbstractModalDialog {
 		
 		// create a separate event loop
 		Display display = Display.getCurrent();
-		while (!shell.isDisposed()) {
+		while (shell != null && !shell.isDisposed()) {
 			if (!display.readAndDispatch()) 
 				display.sleep();
 		}
-		
-		// destroy the window
-		shell.dispose();
+		// forget the reference to the shell (this class is reused in the container)
+		shell = null;
 	}
 	
 	/**
diff --git a/src/net/azib/ipscan/gui/StatisticsDialog.java b/src/net/azib/ipscan/gui/StatisticsDialog.java
index 8113f07e..3645bc15 100644
--- a/src/net/azib/ipscan/gui/StatisticsDialog.java
+++ b/src/net/azib/ipscan/gui/StatisticsDialog.java
@@ -54,6 +54,12 @@ public class StatisticsDialog extends AbstractModalDialog {
 	 * This method initializes shell
 	 */
 	private void createShell() {
+		if (shell != null) {
+			// close the same window if it is already open ('scanning incomplete')
+			shell.close();
+			shell.dispose();
+		}
+		
 		Display currentDisplay = Display.getCurrent();
 		Shell parent = currentDisplay.getShells()[0];
 		shell = new Shell(parent, SWT.APPLICATION_MODAL | SWT.DIALOG_TRIM);