diff --git a/plugins/relaxng/src/org/intellij/plugins/relaxNG/config/NoNamespaceSchemaProvider.java b/plugins/relaxng/src/org/intellij/plugins/relaxNG/config/NoNamespaceSchemaProvider.java
index 556b68eb7c98..db4054aca590 100644
--- a/plugins/relaxng/src/org/intellij/plugins/relaxNG/config/NoNamespaceSchemaProvider.java
+++ b/plugins/relaxng/src/org/intellij/plugins/relaxNG/config/NoNamespaceSchemaProvider.java
@@ -50,6 +50,10 @@ public class NoNamespaceSchemaProvider extends XmlSchemaProvider {
 
   @Override
   public boolean isAvailable(@NotNull XmlFile file) {
-    return file.getFileType() == XmlFileType.INSTANCE;
+    if (file.getFileType() != XmlFileType.INSTANCE) {
+      return false;
+    }
+    NoNamespaceConfig config = NoNamespaceConfig.getInstance(file.getProject());
+    return config != null && config.getMappedFile(file) != null;
   }
 }
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