diff --git a/org.jcryptool.analysis.friedman/src/org/jcryptool/analysis/friedman/ui/FriedmanGraphUI.java b/org.jcryptool.analysis.friedman/src/org/jcryptool/analysis/friedman/ui/FriedmanGraphUI.java
index 535526a40..62c72c1dd 100644
--- a/org.jcryptool.analysis.friedman/src/org/jcryptool/analysis/friedman/ui/FriedmanGraphUI.java
+++ b/org.jcryptool.analysis.friedman/src/org/jcryptool/analysis/friedman/ui/FriedmanGraphUI.java
@@ -107,7 +107,11 @@ public void update(Observable o, Object arg) {
 							}
 							else{
 								
-								boolean result = MessageDialog.openQuestion(FriedmanGraphUI.this.getDisplay().getActiveShell(), Messages.FriedmanGraphUI_warning, Messages.FriedmanGraphUI_warning_text);
+								boolean result = 
+										MessageDialog.openQuestion(
+												FriedmanGraphUI.this.getShell(), 
+												Messages.FriedmanGraphUI_warning, Messages.FriedmanGraphUI_warning_text
+												);
 								if(result) {
 									message = textSelector.getText().getText();
 								}