diff --git a/FileManager/src/org/openintents/filemanager/ThumbnailLoader.java b/FileManager/src/org/openintents/filemanager/ThumbnailLoader.java
index 97b28b3d..b2c8127d 100644
--- a/FileManager/src/org/openintents/filemanager/ThumbnailLoader.java
+++ b/FileManager/src/org/openintents/filemanager/ThumbnailLoader.java
@@ -29,6 +29,7 @@
 import java.io.File;
 import java.lang.ref.SoftReference;
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.concurrent.ConcurrentHashMap;
@@ -60,7 +61,7 @@ public class ThumbnailLoader {
     // This gets cleared by the Garbage Collector everytime we get low on memory.
     private ConcurrentHashMap<String, SoftReference<Bitmap>> mSoftBitmapCache;
     private LinkedHashMap<String, Bitmap> mHardBitmapCache;
-    private ArrayList<String> mBlacklist;
+    private List<String> mBlacklist;
 
     /**
      * Used for loading and decoding thumbnails from files.
@@ -82,7 +83,7 @@ public void run() {
         purgeHandler = new Handler();
         mExecutor = new PausableThreadPoolExecutor(POOL_SIZE);
 
-        mBlacklist = new ArrayList<>();
+        mBlacklist = Collections.synchronizedList(new ArrayList<String>());
         mSoftBitmapCache = new ConcurrentHashMap<>(MAX_CACHE_CAPACITY / 2);
         mHardBitmapCache = new LinkedHashMap<String, Bitmap>(MAX_CACHE_CAPACITY / 2, 0.75f, true) {
 
@@ -166,8 +167,6 @@ public void stopPurgeTimer() {
 
     /**
      * Purges the cache every (DELAY_BEFORE_PURGE) milliseconds.
-     *
-     * @see DELAY_BEFORE_PURGE
      */
     private void resetPurgeTimer() {
         purgeHandler.removeCallbacks(purger);
diff --git a/FileManager/src/org/openintents/filemanager/util/CopyHelper.java b/FileManager/src/org/openintents/filemanager/util/CopyHelper.java
index bf42819a..c82a7438 100644
--- a/FileManager/src/org/openintents/filemanager/util/CopyHelper.java
+++ b/FileManager/src/org/openintents/filemanager/util/CopyHelper.java
@@ -134,7 +134,9 @@ private boolean copyFile(File oldFile, File newFile) {
                 // ignore
             }
             try {
-                output.close();
+                if (output != null) {
+                    output.close();
+                }
             } catch (IOException e) {
                 // ignore
             }