diff --git a/src/main/java/ui/TDiagramPanel.java b/src/main/java/ui/TDiagramPanel.java
index c9e2c8278d71f457a9a64b775bae529cc366e2fb..cd3d5dfa169d816ed115732f19a0541e071938ce 100644
--- a/src/main/java/ui/TDiagramPanel.java
+++ b/src/main/java/ui/TDiagramPanel.java
@@ -2591,21 +2591,27 @@ public abstract class TDiagramPanel extends JPanel implements GenericTree {
         for (TGComponent tgc : getAllComponentList()) {
             tgc.resetVerificationResults();
         }
-        for (TMLTask t : mgui.gtm.getTMLMapping().getTMLModeling().getTasks()) {
-            for (TMLActivityElement elem : t.getActivityDiagram().getElements()) {
-                if (elem.getReferenceObject() instanceof TMLADReadChannel){
-                    TMLADReadChannel rc = (TMLADReadChannel) elem.getReferenceObject();
-                    if (rc.getAuthCheck()) {
-                        rc.setWeakAuthStatus(1);
-                        rc.setStrongAuthStatus(1);
-                    }
-                }
+        if (mgui.gtm.getTMLMapping() != null) {
+            if ( mgui.gtm.getTMLMapping().getTMLModeling() != null) {
+                if (mgui.gtm.getTMLMapping().getTMLModeling().getTasks() != null) {
+                    for (TMLTask t : mgui.gtm.getTMLMapping().getTMLModeling().getTasks()) {
+                        for (TMLActivityElement elem : t.getActivityDiagram().getElements()) {
+                            if (elem.getReferenceObject() instanceof TMLADReadChannel) {
+                                TMLADReadChannel rc = (TMLADReadChannel) elem.getReferenceObject();
+                                if (rc.getAuthCheck()) {
+                                    rc.setWeakAuthStatus(1);
+                                    rc.setStrongAuthStatus(1);
+                                }
+                            }
 
-                if (elem.getReferenceObject() instanceof TMLADDecrypt) {
-                    TMLADDecrypt dec = (TMLADDecrypt) elem.getReferenceObject();
-                    if (dec.getAuthCheck()) {
-                        dec.setWeakAuthStatus(1);
-                        dec.setStrongAuthStatus(1);
+                            if (elem.getReferenceObject() instanceof TMLADDecrypt) {
+                                TMLADDecrypt dec = (TMLADDecrypt) elem.getReferenceObject();
+                                if (dec.getAuthCheck()) {
+                                    dec.setWeakAuthStatus(1);
+                                    dec.setStrongAuthStatus(1);
+                                }
+                            }
+                        }
                     }
                 }
             }