diff -r 7cb7f717f5d0 openide.filesystems/test/unit/src/org/openide/filesystems/MultiFileSystemRefreshTest.java
--- a/openide.filesystems/test/unit/src/org/openide/filesystems/MultiFileSystemRefreshTest.java	Mon Nov 14 16:21:41 2011 +0100
+++ b/openide.filesystems/test/unit/src/org/openide/filesystems/MultiFileSystemRefreshTest.java	Mon Nov 14 21:45:47 2011 +0100
@@ -44,8 +44,8 @@
 
 package org.openide.filesystems;
 
+import java.io.File;
 import org.netbeans.junit.*;
-import junit.textui.TestRunner;
 
 /**
  * Test that MultiFileSystem does not refresh more than it needs to
@@ -59,11 +59,8 @@
         super(name);
     }
 
-    public static void main(String[] args) {
-        TestRunner.run(new NbTestSuite(MultiFileSystemRefreshTest.class));
-    }
-
     private FileSystem fs1, fs2;
+    @Override
     protected void setUp() throws Exception {
         super.setUp();
         fs1 = TestUtilHid.createLocalFileSystem("mfsrefresh1"+getName() + "1", new String[] {
@@ -75,6 +72,7 @@
             "e/g.txt",
         });
     }
+    @Override
     protected void tearDown() throws Exception {
         TestUtilHid.destroyLocalFileSystem(getName() + "1");
         TestUtilHid.destroyLocalFileSystem(getName() + "2");
@@ -117,6 +115,23 @@
         assertEquals(1, e.getChildren().length);
         assertEquals(1, count);
     }
+
+    public void testRefreshMissingRoot() throws Exception {
+        LocalFileSystem fs = new LocalFileSystem();
+        clearWorkDir();
+        fs.setRootDirectory(getWorkDir());
+        
+        MultiFileSystem mfs = new MultiFileSystem(fs1, fs2, fs);
+        FileObject b = mfs.findResource("a/b");
+        assertNotNull(b);
+        assertEquals(2, b.getChildren().length);
+        File x = new File(new File(new File(getWorkDir(), "a"), "b"), "x.txt");
+        x.getParentFile().mkdirs();
+        assertTrue("File created", x.createNewFile());
+        b.refresh();
+// fixes the refresh:        b.getFileSystem().refresh(true);
+        assertEquals("Three now", 3, b.getChildren().length);
+    }
     
     public void fileAttributeChanged(FileAttributeEvent fe) {
         System.err.println("attr changed: " + fe);