diff --git a/scripts/common.py b/scripts/common.py
index f2e98204..ad7f944c 100644
--- a/scripts/common.py
+++ b/scripts/common.py
@@ -411,10 +411,14 @@ def list_registered_platforms(
 
     Only registered platforms generate packs and appear in CI.
     Unregistered YAMLs (e.g., emulatorjs.yml) are base configs for inheritance.
+
+    A missing registry, or a registered platform whose file is gone, raises:
+    left out quietly, verify --all --strict and every --all build passed
+    having checked none of it, and install.py kept serving its last manifest.
     """
     registry_path = os.path.join(platforms_dir, "_registry.yml")
     if not os.path.exists(registry_path):
-        return []
+        raise FileNotFoundError(f"no platform registry at {registry_path}")
     with open(registry_path) as f:
         registry = yaml_load(f) or {}
     platforms = []
@@ -423,8 +427,11 @@ def list_registered_platforms(
         if status == "archived" and not include_archived:
             continue
         config_path = os.path.join(platforms_dir, meta.get("config", f"{name}.yml"))
-        if os.path.exists(config_path):
-            platforms.append(name)
+        if not os.path.exists(config_path):
+            raise FileNotFoundError(
+                f"{name} is registered in {registry_path} but {config_path} does not exist"
+            )
+        platforms.append(name)
     return platforms
 
 
diff --git a/tests/test_audit_regressions.py b/tests/test_audit_regressions.py
index 9974e252..4418c94e 100644
--- a/tests/test_audit_regressions.py
+++ b/tests/test_audit_regressions.py
@@ -5355,5 +5355,24 @@ class ThePackCheckAppliesTheFrontendRule(unittest.TestCase):
                 self.assertIsNotNone(_check_member_hash(zf, "bios/x.bin", entry, "md5"))
 
 
+class ABrokenRegistryIsNotAnEmptyOne(unittest.TestCase):
+    """A registered platform whose YAML was renamed was skipped without a
+    word, and a missing registry read as no platforms: verify --all --strict
+    and every --all build passed having checked nothing."""
+
+    def test_both_raise(self):
+        from scripts.common import list_registered_platforms
+
+        with tempfile.TemporaryDirectory(dir=TMP_ROOT) as tmp:
+            with self.assertRaises(FileNotFoundError):
+                list_registered_platforms(tmp)
+            Path(tmp, "_registry.yml").write_text(
+                "platforms:\n  rocknix:\n    config: rocknix.yml\n", encoding="utf-8"
+            )
+            with self.assertRaises(FileNotFoundError) as caught:
+                list_registered_platforms(tmp)
+            self.assertIn("rocknix", str(caught.exception))
+
+
 if __name__ == "__main__":
     unittest.main()