diff --git a/modules/node/node.install b/modules/node/node.install
index 76c2aec..0b0a7bd 100644
--- a/modules/node/node.install
+++ b/modules/node/node.install
@@ -934,5 +934,15 @@ function node_update_7014() {
 }
 
 /**
+ * Enable node types that may have been erroneously disabled in Drupal 7.36.
+ */
+function node_update_7015() {
+  db_update('node_type')
+    ->fields(array('disabled' => 0))
+    ->condition('base', 'node_content')
+    ->execute();
+}
+
+/**
  * @} End of "addtogroup updates-7.x-extra".
  */
diff --git a/modules/node/node.module b/modules/node/node.module
index fd848e2..7a6246d 100644
--- a/modules/node/node.module
+++ b/modules/node/node.module
@@ -740,9 +740,11 @@ function _node_types_build($rebuild = FALSE) {
     $type_db = $type_object->type;
     // Original disabled value.
     $disabled = $type_object->disabled;
-    // Check for node types either from disabled modules or otherwise not defined
-    // and mark as disabled.
-    if (empty($type_object->custom) && empty($_node_types->types[$type_db])) {
+    // Check for node types from disabled modules and mark their types for removal.
+    // Types defined by the node module in the database (rather than by a separate
+    // module using hook_node_info) have a base value of 'node_content'. The isset()
+    // check prevents errors on old (pre-Drupal 7) databases.
+    if (isset($type_object->base) && $type_object->base != 'node_content' && empty($_node_types->types[$type_db])) {
       $type_object->disabled = TRUE;
     }
     if (isset($_node_types->types[$type_db])) {