diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index a6c9f7007..ea246a06d 100644
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -1,8 +1,8 @@
 <?xml version="1.0" encoding="utf-8"?>
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
     package="com.hippo.ehviewer"
-    android:versionCode="11"
-    android:versionName="0.4.1" >
+    android:versionCode="12"
+    android:versionName="0.4.2" >
     
     <uses-sdk
         android:minSdkVersion="14"
diff --git a/bin/AndroidManifest.xml b/bin/AndroidManifest.xml
index a6c9f7007..ea246a06d 100644
--- a/bin/AndroidManifest.xml
+++ b/bin/AndroidManifest.xml
@@ -1,8 +1,8 @@
 <?xml version="1.0" encoding="utf-8"?>
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
     package="com.hippo.ehviewer"
-    android:versionCode="11"
-    android:versionName="0.4.1" >
+    android:versionCode="12"
+    android:versionName="0.4.2" >
     
     <uses-sdk
         android:minSdkVersion="14"
diff --git a/bin/EhViewer.apk b/bin/EhViewer.apk
index 0c5272eeb..3b7308e4f 100644
Binary files a/bin/EhViewer.apk and b/bin/EhViewer.apk differ
diff --git a/bin/classes.dex b/bin/classes.dex
index bbb241cc0..c166338f9 100644
Binary files a/bin/classes.dex and b/bin/classes.dex differ
diff --git a/bin/resources.ap_ b/bin/resources.ap_
index 8c18eb74f..14734e751 100644
Binary files a/bin/resources.ap_ and b/bin/resources.ap_ differ
diff --git a/res/raw/change_log b/res/raw/change_log
index e860e1a34..722db58ad 100644
--- a/res/raw/change_log
+++ b/res/raw/change_log
@@ -1,3 +1,6 @@
+Version 0.4.2 (2014-??-??)
+* 添加内置存储空间或 Sd Card 检测
+
 Version 0.4.1 (2014-04-02)
 * 修正单点触控缩放错误
 * 修正下载完毕后无法读取最后一页
diff --git a/src/com/hippo/ehviewer/ImageLoadManager.java b/src/com/hippo/ehviewer/ImageLoadManager.java
index 43362e263..56cce55a1 100644
--- a/src/com/hippo/ehviewer/ImageLoadManager.java
+++ b/src/com/hippo/ehviewer/ImageLoadManager.java
@@ -78,10 +78,11 @@ public class ImageLoadManager {
                 }
                 LoadImageView liv = curLoadTask.liv;
                 String key = liv.getKey();
-                Bitmap bitmap;
-                if ((bitmap = mMemoryCache.get(key)) == null) {
-                    bitmap = (Bitmap)mDiskCache.get(key, Util.BITMAP);
-                    if (bitmap != null)
+                Bitmap bitmap = null;
+                if (mMemoryCache == null || (bitmap = mMemoryCache.get(key)) == null) {
+                    if (mDiskCache != null
+                            && (bitmap = (Bitmap)mDiskCache.get(key, Util.BITMAP)) != null
+                            && mMemoryCache != null)
                         mMemoryCache.put(key, bitmap);
                 }
                 
diff --git a/src/com/hippo/ehviewer/StartActivity.java b/src/com/hippo/ehviewer/StartActivity.java
index 95a46dd80..0e3c78889 100644
--- a/src/com/hippo/ehviewer/StartActivity.java
+++ b/src/com/hippo/ehviewer/StartActivity.java
@@ -1,6 +1,7 @@
 package com.hippo.ehviewer;
 
 import com.hippo.ehviewer.activity.MangaListActivity;
+import com.hippo.ehviewer.util.Cache;
 import com.hippo.ehviewer.util.Config;
 import com.hippo.ehviewer.util.Crash;
 import com.hippo.ehviewer.view.AlertButton;
@@ -26,8 +27,10 @@ import android.widget.RelativeLayout;
 public class StartActivity extends Activity {
     
     private static final int CHECK_WARING = 0;
-    private static final int CHECK_CRESH = 1;
-    private static final int CHECK_NETWORK = 2;
+    private static final int CHECK_NETWORK = 1;
+    private static final int CHECK_CRASH = 2;
+    private static final int CHECK_EXTERNAL_STORAGE = 3;
+    
     
     private String lastCrash;
     private boolean isAnimationOver = false;
@@ -65,7 +68,7 @@ public class StartActivity extends Activity {
                     public void onClick(View v) {
                         ((AlertButton)v).dialog.dismiss();
                         
-                        check(CHECK_CRESH);
+                        check(CHECK_CRASH);
                     }
                 })
                 .setNegativeButton(R.string.dailog_network_error_no,
@@ -95,7 +98,8 @@ public class StartActivity extends Activity {
                                             @Override
                                             public void onClick(View v) {
                                                 ((AlertButton)v).dialog.dismiss();
-                                                checkOver();
+                                                
+                                                check(CHECK_EXTERNAL_STORAGE);
                                             }
                                         }).show();
                         
@@ -113,8 +117,28 @@ public class StartActivity extends Activity {
                         ((AlertButton)v).dialog.dismiss();
                         lastCrash = null;
                         
+                        check(CHECK_EXTERNAL_STORAGE);
+                    }
+                }).create();
+    }
+    
+    private AlertDialog createNoSdCardDialog() {
+        return new DialogBuilder(this).setCancelable(false)
+                .setTitle("未检测到内置存储空间或 Sd Card")
+                .setMessage("未检测到内置存储空间或 Sd Card，您无法使用磁盘缓存与下载功能，用户体验会很糟，是否继续？")
+                .setPositiveButton("我不介意", new View.OnClickListener() {
+                    @Override
+                    public void onClick(View v) {
+                        ((AlertButton)v).dialog.dismiss();
+                        
                         checkOver();
                     }
+                }).setNegativeButton("算了", new View.OnClickListener() {
+                    @Override
+                    public void onClick(View v) {
+                        ((AlertButton)v).dialog.dismiss();
+                        finish();
+                    }
                 }).create();
     }
     
@@ -158,6 +182,15 @@ public class StartActivity extends Activity {
         check(CHECK_WARING);
     }
     
+    /**
+     * Order is
+     * 1. check waring
+     * 2. check network
+     * 3. check crash
+     * 4. check external storage
+     * 
+     * @param order
+     */
     private void check(int order) {
         switch (order) {
         case CHECK_WARING:
@@ -170,11 +203,16 @@ public class StartActivity extends Activity {
                 createNetworkErrorDialog().show();
                 return;
             }
-        case CHECK_CRESH:
+        case CHECK_CRASH:
             if ((lastCrash = Crash.getLastCrash()) != null) {
                 createSendCrashDialog().show();
                 return;
             }
+        case CHECK_EXTERNAL_STORAGE:
+            if (!Cache.hasSdCard()) {
+                createNoSdCardDialog().show();
+                return;
+            }
         }
         checkOver();
     }
diff --git a/src/com/hippo/ehviewer/gallery/data/ImageSet.java b/src/com/hippo/ehviewer/gallery/data/ImageSet.java
index f923b26f8..cc60e0cc4 100644
--- a/src/com/hippo/ehviewer/gallery/data/ImageSet.java
+++ b/src/com/hippo/ehviewer/gallery/data/ImageSet.java
@@ -75,7 +75,9 @@ public class ImageSet {
             throw new IllegalArgumentException("Folder is null or not directory");
         if (size < 0 || startIndex < 0
                 || startIndex > endIndex || endIndex > size)
-            throw new IllegalArgumentException("size or index value error");
+            throw new IllegalArgumentException("size or index value error, size = "
+                + size + ", startIndex = " + startIndex
+                + ", endIndex" + endIndex);
         
         mContext = context;
         mGid = gid;