diff --git a/src/Tasks/GenerateRegistryPassThrough.cs b/src/Tasks/GenerateRegistryPassThrough.cs
index bb1f5fb..c1f0174 100644
--- a/src/Tasks/GenerateRegistryPassThrough.cs
+++ b/src/Tasks/GenerateRegistryPassThrough.cs
@@ -40,11 +40,13 @@ public class GenerateRegistryPassThrough : PoloniumTask
                 .DescendantNodes()
                 .OfType<ClassDeclarationSyntax>()
                 .FirstOrDefault(cls => cls.Identifier.Text == "PoloniumRegistry");
-            IEnumerable<PropertyDeclarationSyntax> properties = clas!.Members
+            IEnumerable<PropertyDeclarationSyntax> properties = clas?.Members
                 .OfType<PropertyDeclarationSyntax>()
                 .Where(m => m.AttributeLists
                     .SelectMany(a => a.Attributes)
                     .Any(a => a.Name.ToString() == "RegistryPassThrough"));
+            if (properties is null)
+                return false;
             foreach (PropertyDeclarationSyntax property in properties)
             {
                 if (HasGetterOnly(property))