diff --git a/platform/platform-impl/src/com/intellij/openapi/components/impl/stores/StateStorageManagerImpl.java b/platform/platform-impl/src/com/intellij/openapi/components/impl/stores/StateStorageManagerImpl.java
index bcbf5630e755..36c993fe3527 100644
--- a/platform/platform-impl/src/com/intellij/openapi/components/impl/stores/StateStorageManagerImpl.java
+++ b/platform/platform-impl/src/com/intellij/openapi/components/impl/stores/StateStorageManagerImpl.java
@@ -23,6 +23,7 @@ import com.intellij.openapi.options.StreamProvider;
 import com.intellij.openapi.util.Disposer;
 import com.intellij.openapi.util.JDOMUtil;
 import com.intellij.openapi.util.Pair;
+import com.intellij.openapi.util.io.FileUtil;
 import com.intellij.openapi.util.text.StringUtil;
 import com.intellij.openapi.vfs.VirtualFile;
 import com.intellij.util.containers.MultiMap;
@@ -267,6 +268,11 @@ public abstract class StateStorageManagerImpl implements StateStorageManager, Di
       return null;
     }
 
+    final String extension = FileUtil.getExtension(new File(expandedFile).getName());
+    if (extension.length() == 0) {
+      throw new IllegalArgumentException("Extension is missing for storage file: " + expandedFile);
+    }
+
     return createFileStateStorage(fileSpec, expandedFile, myRootTagName, myPicoContainer);
   }