diff --git a/app/src/main/java/us/shandian/giga/util/Utility.java b/app/src/main/java/us/shandian/giga/util/Utility.java
index 29720786f..774edd0bc 100644
--- a/app/src/main/java/us/shandian/giga/util/Utility.java
+++ b/app/src/main/java/us/shandian/giga/util/Utility.java
@@ -141,16 +141,7 @@ public class Utility
 
 		}
 	}
-	
-	public static String getErrorString(Context context, int code) {
-		switch (code) {
-			case DownloadMission.ERROR_SERVER_UNSUPPORTED:
-				return context.getString(R.string.msg_server_unsupported);
-			default:
-				return "";
-		}
-	}
-	
+
 	public static FileType getFileType(String file) {
 		if (file.endsWith(".apk")) {
 			return FileType.APP;
diff --git a/app/src/main/res/drawable-hdpi/drawer_shadow.9.png b/app/src/main/res/drawable-hdpi/drawer_shadow.9.png
deleted file mode 100644
index 236bff558..000000000
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diff --git a/app/src/main/res/drawable-hdpi/ic_add_white_24dp.png b/app/src/main/res/drawable-hdpi/ic_add_white_24dp.png
deleted file mode 100644
index 481643ecd..000000000
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diff --git a/app/src/main/res/drawable-ldrtl-xhdpi/apps.png b/app/src/main/res/drawable-ldrtl-xhdpi/apps.png
deleted file mode 100644
index 27a31e90f..000000000
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diff --git a/app/src/main/res/drawable-ldrtl-xhdpi/archive.png b/app/src/main/res/drawable-ldrtl-xhdpi/archive.png
deleted file mode 100644
index 70ba10c53..000000000
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diff --git a/app/src/main/res/drawable-ldrtl-xhdpi/drawer_shadow.9.png b/app/src/main/res/drawable-ldrtl-xhdpi/drawer_shadow.9.png
deleted file mode 100644
index fabe9d965..000000000
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diff --git a/app/src/main/res/drawable-ldrtl-xhdpi/excel.png b/app/src/main/res/drawable-ldrtl-xhdpi/excel.png
deleted file mode 100644
index fe19a6500..000000000
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diff --git a/app/src/main/res/drawable-ldrtl-xhdpi/ic_add_white_24dp.png b/app/src/main/res/drawable-ldrtl-xhdpi/ic_add_white_24dp.png
deleted file mode 100644
index 67042105d..000000000
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diff --git a/app/src/main/res/drawable-ldrtl-xhdpi/music.png b/app/src/main/res/drawable-ldrtl-xhdpi/music.png
deleted file mode 100644
index 130f5da30..000000000
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diff --git a/app/src/main/res/drawable-ldrtl-xhdpi/pdf.png b/app/src/main/res/drawable-ldrtl-xhdpi/pdf.png
deleted file mode 100644
index 9b8005b1f..000000000
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diff --git a/app/src/main/res/drawable-ldrtl-xhdpi/powerpoint.png b/app/src/main/res/drawable-ldrtl-xhdpi/powerpoint.png
deleted file mode 100644
index 7d6ca29bc..000000000
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diff --git a/app/src/main/res/drawable-ldrtl-xhdpi/unknown.png b/app/src/main/res/drawable-ldrtl-xhdpi/unknown.png
deleted file mode 100644
index 5e535f265..000000000
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diff --git a/app/src/main/res/drawable-ldrtl-xhdpi/video.png b/app/src/main/res/drawable-ldrtl-xhdpi/video.png
deleted file mode 100644
index fefb72d9c..000000000
Binary files a/app/src/main/res/drawable-ldrtl-xhdpi/video.png and /dev/null differ
diff --git a/app/src/main/res/drawable-ldrtl-xhdpi/word.png b/app/src/main/res/drawable-ldrtl-xhdpi/word.png
deleted file mode 100644
index 34f3685d8..000000000
Binary files a/app/src/main/res/drawable-ldrtl-xhdpi/word.png and /dev/null differ
diff --git a/app/src/main/res/drawable-xxhdpi/ic_add_white_24dp.png b/app/src/main/res/drawable-xxhdpi/ic_add_white_24dp.png
deleted file mode 100644
index 72cedcad4..000000000
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