diff --git a/WGneu/Windows/MemberListWindow.xaml.cs b/WGneu/Windows/MemberListWindow.xaml.cs
index db467f9..f94e7b0 100644
--- a/WGneu/Windows/MemberListWindow.xaml.cs
+++ b/WGneu/Windows/MemberListWindow.xaml.cs
@@ -47,9 +47,10 @@ namespace WGneu.Windows {
 
         private int CountMatchesInMember(Member m) {
             if (TextFilter.Count == 0) return 0;
-            string[] check = new string[] { m.MgNr.ToString(), m.FamilyName.ToLower(), m.GivenName.ToLower(), m.DefaultKg.Name.ToLower() };
+            string?[] check = new string?[] { m.MgNr.ToString(), m.FamilyName.ToLower(), m.GivenName.ToLower(), m.DefaultKg?.Name?.ToLower() };
             int i = 0;
-            foreach (string c in check) {
+            foreach (string? c in check) {
+                if (c == null) continue;
                 if (TextFilter.Any(f => c == f))
                     i += 10;
                 else if (TextFilter.Any(f => c.Contains(f)))