diff --git a/EduNetworkBuilder/PersonProfileForm.cs b/EduNetworkBuilder/PersonProfileForm.cs
index 3e35917..9b61743 100644
--- a/EduNetworkBuilder/PersonProfileForm.cs
+++ b/EduNetworkBuilder/PersonProfileForm.cs
@@ -451,6 +451,7 @@ namespace EduNetworkBuilder
             if (tvClasswork.SelectedNode == null) return;
 
             TreeNode Node = tvClasswork.SelectedNode;
+            if (Node == null) return; //Break out to avoid exploding
 
             if (Node.Tag is SchoolworkClass)
             {