diff --git a/gen-custom-android-build.py b/gen-custom-android-build.py
index 87e868c43..68ed447b9 100755
--- a/gen-custom-android-build.py
+++ b/gen-custom-android-build.py
@@ -460,11 +460,10 @@ def step_embed_zimfile(jsdata, **options):
         os.symlink('../{}/{}'.format(archs[0], jsdata.get('zim_name')),
                    jsdata.get('zim_name'))
     os.chdir(tmpd)
-    syscall('zip -r -0 {} lib'
+    syscall('zip -r -0 -y {} lib'
             .format(os.path.join(ANDROID_PATH, 'content-libs.jar')))
     shutil.rmtree(tmpd)
 
-
 def step_build_apk(jsdata, **options):
     ''' build the actual APK '''
 
diff --git a/src/org/kiwix/kiwixmobile/KiwixMobileActivity.java b/src/org/kiwix/kiwixmobile/KiwixMobileActivity.java
index 46b0f97fb..58999abc8 100644
--- a/src/org/kiwix/kiwixmobile/KiwixMobileActivity.java
+++ b/src/org/kiwix/kiwixmobile/KiwixMobileActivity.java
@@ -1123,11 +1123,8 @@ public class KiwixMobileActivity extends AppCompatActivity
             filePath = FileUtils.generateSaveFileName(fileName);
           }
 
-          Log.d(TAG_KIWIX, "Looking for: " + filePath + " -- filesize: "
-              + Constants.CUSTOM_APP_ZIM_FILE_SIZE);
           if (!FileUtils
               .doesFileExist(filePath, Constants.CUSTOM_APP_ZIM_FILE_SIZE, false)) {
-            Log.d(TAG_KIWIX, "... doesn't exist.");
 
             AlertDialog.Builder zimFileMissingBuilder = new AlertDialog.Builder(
                 this);
diff --git a/src/org/kiwix/kiwixmobile/utils/files/FileUtils.java b/src/org/kiwix/kiwixmobile/utils/files/FileUtils.java
index bb891c24a..ee45e2cbe 100644
--- a/src/org/kiwix/kiwixmobile/utils/files/FileUtils.java
+++ b/src/org/kiwix/kiwixmobile/utils/files/FileUtils.java
@@ -1,5 +1,6 @@
 package org.kiwix.kiwixmobile.utils.files;
 
+import android.util.Log;
 import android.content.Context;
 import android.os.Environment;
 import java.io.File;
@@ -7,6 +8,8 @@ import org.kiwix.kiwixmobile.settings.Constants;
 
 public class FileUtils {
 
+  public static final String TAG_KIWIX = "kiwix";
+
   public static File getFileCacheDir(Context context) {
     boolean external = Environment.MEDIA_MOUNTED.equals(Environment.getExternalStorageState());
 
@@ -61,18 +64,27 @@ public class FileUtils {
    */
   static public boolean doesFileExist(String fileName, long fileSize,
       boolean deleteFileOnMismatch) {
+
+    Log.d(TAG_KIWIX, "Looking for '" + fileName + "' with size=" + fileSize);
+
     // the file may have been delivered by Market --- let's make sure
     // it's the size we expect
     File fileForNewFile = new File(fileName);
     if (fileForNewFile.exists()) {
       if (fileForNewFile.length() == fileSize) {
+        Log.d(TAG_KIWIX, "Correct file '" + fileName + "' found.");
         return true;
+      } else {
+        Log.d(TAG_KIWIX, "File '" + fileName + "' found but with wrong size=" + fileForNewFile.length());
       }
+
       if (deleteFileOnMismatch) {
         // delete the file --- we won't be able to resume
         // because we cannot confirm the integrity of the file
         fileForNewFile.delete();
       }
+    } else {
+      Log.d(TAG_KIWIX, "No file '" + fileName + "' found.");
     }
     return false;
   }