diff --git a/app/build.gradle b/app/build.gradle
index 030bd12..5924a4c 100755
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -7,8 +7,8 @@ android {
         minSdkVersion 19
         targetSdkVersion 28
         multiDexEnabled true
-        versionCode 152200304
-        versionName "1.5.2"
+        versionCode 153200308
+        versionName "1.5.3"
         externalNativeBuild {
             cmake {
                 cppFlags "-std=c++11 -pthread -frtti -fexceptions"
diff --git a/app/src/main/java/it/pgp/xfiles/service/BaseBackgroundTask.java b/app/src/main/java/it/pgp/xfiles/service/BaseBackgroundTask.java
index 923f9c5..e36cf65 100755
--- a/app/src/main/java/it/pgp/xfiles/service/BaseBackgroundTask.java
+++ b/app/src/main/java/it/pgp/xfiles/service/BaseBackgroundTask.java
@@ -8,8 +8,8 @@
 import android.view.WindowManager;
 
 import java.io.Serializable;
-import java.util.ArrayDeque;
 import java.util.Deque;
+import java.util.concurrent.ConcurrentLinkedDeque;
 
 import it.pgp.xfiles.enums.FileOpsErrorCodes;
 import it.pgp.xfiles.enums.ForegroundServiceType;
@@ -32,7 +32,7 @@ public abstract class BaseBackgroundTask extends AsyncTask<Object,Integer,Object
 
     public Serializable params; // to be down-casted in subclasses
 
-    public static final Deque<Runnable> nextAutoTasks = new ArrayDeque<>();
+    public static final Deque<Runnable> nextAutoTasks = new ConcurrentLinkedDeque<>();
 
     public BaseBackgroundTask(Serializable params) {
         this.params = params;
@@ -115,8 +115,14 @@ protected void onPostExecute(Object o) {
         ProgressIndicator.release();
 
         if(!nextAutoTasks.isEmpty()) {
-            Log.d(getClass().getName(),"Starting next auto task...");
-            new Thread(nextAutoTasks.pop()).start();
+            if(result == null || result == FileOpsErrorCodes.OK) {
+                Log.d(getClass().getName(),"Starting next auto task...");
+                new Thread(nextAutoTasks.pop()).start();
+            }
+            else {
+                Log.d(getClass().getName(),"Current task failed, clearing next auto tasks...");
+                nextAutoTasks.clear();
+            }
         }
     }