diff --git a/platform/lang-impl/src/com/intellij/ide/extensionResources/ResourceVersions.java b/platform/lang-impl/src/com/intellij/ide/extensionResources/ResourceVersions.java
index 098c65746b04..af3f1b6d99cb 100644
--- a/platform/lang-impl/src/com/intellij/ide/extensionResources/ResourceVersions.java
+++ b/platform/lang-impl/src/com/intellij/ide/extensionResources/ResourceVersions.java
@@ -100,8 +100,10 @@ class ResourceVersions implements PersistentStateComponent<ResourceVersions.Stat
       return null;
     }
 
+    @NotNull
     private static String getId(@NotNull IdeaPluginDescriptor plugin) {
-      return plugin.isBundled() ? PluginManagerCore.CORE_PLUGIN_ID : plugin.getPluginId().getIdString();
+      PluginId pluginId = plugin.getPluginId();
+      return pluginId != null ? pluginId.getIdString() : PluginManagerCore.CORE_PLUGIN_ID;
     }
 
     @NotNull