diff --git a/Duplicati/UnitTest/RemoteSynchronizationModuleTests.cs b/Duplicati/UnitTest/RemoteSynchronizationModuleTests.cs
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+// Copyright (C) 2025, The Duplicati Team
+// https://duplicati.com, hello@duplicati.com
+//
+// Permission is hereby granted, free of charge, to any person obtaining a
+// copy of this software and associated documentation files (the "Software"),
+// to deal in the Software without restriction, including without limitation
+// the rights to use, copy, modify, merge, publish, distribute, sublicense,
+// and/or sell copies of the Software, and to permit persons to whom the
+// Software is furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+// DEALINGS IN THE SOFTWARE.
+
+using Duplicati.Library.Modules.Builtin;
+using Duplicati.Library.Interface;
+using Duplicati.Library.Utility;
+using Duplicati.Library.Main;
+using NUnit.Framework;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using Duplicati.Library.Main.Database;
+using Duplicati.Library.SQLiteHelper;
+using Assert = NUnit.Framework.Legacy.ClassicAssert;
+
+namespace Duplicati.UnitTest
+{
+    [TestFixture]
+    public class RemoteSynchronizationModuleTests : BasicSetupHelper
+    {
+        [Test]
+        [Category("RemoteSync")]
+        public void TestConfigure_SingleDestination()
+        {
+            var module = new RemoteSynchronizationModule();
+            var options = new Dictionary<string, string>
+            {
+                ["remote-sync-dst"] = "file:///test/dest"
+            };
+
+            module.Configure(options);
+
+            var destinations = module.GetType().GetField("m_destinations", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance).GetValue(module) as List<string>;
+            Assert.AreEqual(1, destinations.Count);
+            Assert.AreEqual("file:///test/dest", destinations[0]);
+        }
+
+        [Test]
+        [Category("RemoteSync")]
+        public void TestConfigure_MultipleDestinations()
+        {
+            var module = new RemoteSynchronizationModule();
+            var options = new Dictionary<string, string>
+            {
+                ["remote-sync-dst"] = "file:///test/dest1,file:///test/dest2"
+            };
+
+            module.Configure(options);
+
+            var destinations = module.GetType().GetField("m_destinations", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance).GetValue(module) as List<string>;
+            Assert.AreEqual(2, destinations.Count);
+            Assert.AreEqual("file:///test/dest1", destinations[0]);
+            Assert.AreEqual("file:///test/dest2", destinations[1]);
+        }
+
+        [Test]
+        [Category("RemoteSync")]
+        public void TestConfigure_Modes()
+        {
+            var module = new RemoteSynchronizationModule();
+            var options = new Dictionary<string, string>
+            {
+                ["remote-sync-dst"] = "file:///test/dest1,file:///test/dest2",
+                ["remote-sync-mode"] = "inline,scheduled"
+            };
+
+            module.Configure(options);
+
+            var modes = module.GetType().GetField("m_modes", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance).GetValue(module) as List<RemoteSyncTriggerMode>;
+            Assert.AreEqual(2, modes.Count);
+            Assert.AreEqual(RemoteSyncTriggerMode.Inline, modes[0]);
+            Assert.AreEqual(RemoteSyncTriggerMode.Scheduled, modes[1]);
+        }
+
+        [Test]
+        [Category("RemoteSync")]
+        public void TestConfigure_Schedules()
+        {
+            var module = new RemoteSynchronizationModule();
+            var options = new Dictionary<string, string>
+            {
+                ["remote-sync-dst"] = "file:///test/dest1,file:///test/dest2",
+                ["remote-sync-schedule"] = "1:00:00,2:00:00"
+            };
+
+            module.Configure(options);
+
+            var schedules = module.GetType().GetField("m_schedules", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance).GetValue(module) as List<TimeSpan>;
+            Assert.AreEqual(2, schedules.Count);
+            Assert.AreEqual(TimeSpan.FromHours(1), schedules[0]);
+            Assert.AreEqual(TimeSpan.FromHours(2), schedules[1]);
+        }
+
+        [Test]
+        [Category("RemoteSync")]
+        public void TestConfigure_Counts()
+        {
+            var module = new RemoteSynchronizationModule();
+            var options = new Dictionary<string, string>
+            {
+                ["remote-sync-dst"] = "file:///test/dest1,file:///test/dest2",
+                ["remote-sync-count"] = "5,10"
+            };
+
+            module.Configure(options);
+
+            var counts = module.GetType().GetField("m_counts", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance).GetValue(module) as List<int>;
+            Assert.AreEqual(2, counts.Count);
+            Assert.AreEqual(5, counts[0]);
+            Assert.AreEqual(10, counts[1]);
+        }
+
+        [Test]
+        [Category("RemoteSync")]
+        public void TestOnStart_SetsSource()
+        {
+            var module = new RemoteSynchronizationModule();
+            var options = new Dictionary<string, string>
+            {
+                ["remote-sync-dst"] = "file:///test/dest"
+            };
+            module.Configure(options);
+
+            string remoteurl = "file:///source";
+            string[] localpath = new string[0];
+            module.OnStart("Backup", ref remoteurl, ref localpath);
+
+            var source = module.GetType().GetField("m_source", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance).GetValue(module) as string;
+            Assert.AreEqual("file:///source", source);
+        }
+
+        [Test]
+        [Category("RemoteSync")]
+        public void TestShouldTriggerSync_Inline()
+        {
+            var module = new RemoteSynchronizationModule();
+            var options = new Dictionary<string, string>
+            {
+                ["remote-sync-dst"] = "file:///test/dest",
+                ["remote-sync-mode"] = "inline",
+                ["dbpath"] = DBFILE
+            };
+            module.Configure(options);
+
+            var shouldTrigger = (bool)module.GetType().GetMethod("ShouldTriggerSync", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance).Invoke(module, new object[] { 0 });
+            Assert.IsTrue(shouldTrigger);
+        }
+
+        [Test]
+        [Category("RemoteSync")]
+        public void TestShouldTriggerSync_Scheduled_FirstTime()
+        {
+            var module = new RemoteSynchronizationModule();
+            var options = new Dictionary<string, string>
+            {
+                ["remote-sync-dst"] = "file:///test/dest",
+                ["remote-sync-mode"] = "scheduled",
+                ["remote-sync-schedule"] = "1:00:00",
+                ["dbpath"] = DBFILE
+            };
+            module.Configure(options);
+
+            // Create Operation table
+            using var db = SQLiteLoader.LoadConnection(DBFILE);
+            using var cmd = db.CreateCommand();
+            cmd.CommandText = "CREATE TABLE IF NOT EXISTS \"Operation\" (\"Description\" TEXT, \"Timestamp\" INTEGER)";
+            cmd.ExecuteNonQuery();
+
+            var shouldTrigger = (bool)module.GetType().GetMethod("ShouldTriggerSync", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance).Invoke(module, new object[] { 0 });
+            Assert.IsTrue(shouldTrigger);
+        }
+
+        [Test]
+        [Category("RemoteSync")]
+        public void TestShouldTriggerSync_Counting_FirstTime()
+        {
+            var module = new RemoteSynchronizationModule();
+            var options = new Dictionary<string, string>
+            {
+                ["remote-sync-dst"] = "file:///test/dest",
+                ["remote-sync-mode"] = "counting",
+                ["remote-sync-count"] = "2",
+                ["dbpath"] = DBFILE
+            };
+            module.Configure(options);
+
+            // Create Operation table and simulate 2 backups
+            using var db = SQLiteLoader.LoadConnection(DBFILE);
+            using var cmd = db.CreateCommand();
+            cmd.CommandText = "CREATE TABLE IF NOT EXISTS \"Operation\" (\"Description\" TEXT, \"Timestamp\" INTEGER)";
+            cmd.ExecuteNonQuery();
+            cmd.CommandText = "INSERT INTO \"Operation\" (\"Description\", \"Timestamp\") VALUES ('Backup', @ts)";
+            cmd.AddNamedParameter("@ts", Duplicati.Library.Utility.Utility.NormalizeDateTimeToEpochSeconds(DateTime.UtcNow));
+            cmd.ExecuteNonQuery();
+            cmd.ExecuteNonQuery();
+
+            var shouldTrigger = (bool)module.GetType().GetMethod("ShouldTriggerSync", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance).Invoke(module, new object[] { 0 });
+            Assert.IsTrue(shouldTrigger);
+        }
+
+        [Test]
+        [Category("RemoteSync")]
+        public void TestRecordSyncOperation()
+        {
+            var module = new RemoteSynchronizationModule();
+            var options = new Dictionary<string, string>
+            {
+                ["remote-sync-dst"] = "file:///test/dest",
+                ["dbpath"] = DBFILE
+            };
+            module.Configure(options);
+
+            // Create Operation table
+            using var db = SQLiteLoader.LoadConnection(DBFILE);
+            using var cmd = db.CreateCommand();
+            cmd.CommandText = "CREATE TABLE IF NOT EXISTS \"Operation\" (\"Description\" TEXT, \"Timestamp\" INTEGER)";
+            cmd.ExecuteNonQuery();
+
+            module.GetType().GetMethod("RecordSyncOperation", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance).Invoke(module, new object[] { 0 });
+
+            cmd.CommandText = "SELECT COUNT(*) FROM \"Operation\" WHERE \"Description\" = 'Rsync 0'";
+            var count = (long)cmd.ExecuteScalar();
+            Assert.AreEqual(1, count);
+        }
+
+        [Test]
+        [Category("RemoteSync")]
+        public void TestBuildArguments()
+        {
+            var module = new RemoteSynchronizationModule();
+            var options = new Dictionary<string, string>
+            {
+                ["remote-sync-dst"] = "file:///test/dest",
+                ["remote-sync-force"] = "true",
+                ["remote-sync-retention"] = "true"
+            };
+            module.Configure(options);
+
+            // Set m_source
+            module.GetType().GetField("m_source", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance).SetValue(module, "file:///source");
+
+            var args = module.GetType().GetMethod("BuildArguments", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance).Invoke(module, new object[] { "file:///dest" }) as string[];
+
+            Assert.IsTrue(args.Contains("file:///source"));
+            Assert.IsTrue(args.Contains("file:///dest"));
+            Assert.IsTrue(args.Contains("--force"));
+            Assert.IsTrue(args.Contains("--retention"));
+            Assert.IsTrue(args.Contains("--auto-create-folders"));
+        }
+
+        [Test]
+        [Category("RemoteSync")]
+        public void TestOnFinish_SuccessfulBackup_TriggersSync()
+        {
+            // Create some test files
+            System.IO.File.WriteAllText(System.IO.Path.Combine(DATAFOLDER, "testfile.txt"), "test content");
+
+            var options = TestOptions;
+            options["remote-sync-dst"] = "file://" + System.IO.Path.Combine(BASEFOLDER, "syncdest");
+            options["dbpath"] = DBFILE;
+
+            // Run actual backup
+            using (var console = new CommandLine.ConsoleOutput(Console.Out, options))
+            using (var controller = new Duplicati.Library.Main.Controller("file://" + TARGETFOLDER, options, console))
+            {
+                var result = controller.Backup(new string[] { DATAFOLDER });
+
+                // Now check if sync was triggered (assuming module was loaded)
+                // But since we can't easily get the module instance, check if Operation table has sync entry
+                using var db = SQLiteLoader.LoadConnection(DBFILE);
+                using var cmd = db.CreateCommand();
+                cmd.CommandText = "SELECT COUNT(*) FROM \"Operation\" WHERE \"Description\" LIKE 'Rsync %'";
+                var count = (long)cmd.ExecuteScalar();
+                Assert.AreEqual(1, count);
+            }
+        }
+
+        [Test]
+        [Category("RemoteSync")]
+        public void TestOnFinish_FailedBackup_SkipsSync()
+        {
+            var module = new RemoteSynchronizationModule();
+            var options = new Dictionary<string, string>
+            {
+                ["remote-sync-dst"] = "file:///test/dest",
+                ["dbpath"] = DBFILE
+            };
+            module.Configure(options);
+            string remoteurl = "file:///source";
+            string[] localpath = new string[0];
+            module.OnStart("Backup", ref remoteurl, ref localpath);
+
+            // Create Operation table
+            using var db = SQLiteLoader.LoadConnection(DBFILE);
+            using var cmd = db.CreateCommand();
+            cmd.CommandText = "CREATE TABLE IF NOT EXISTS \"Operation\" (\"Description\" TEXT, \"Timestamp\" INTEGER)";
+            cmd.ExecuteNonQuery();
+
+            var result = new TestBasicResults(ParsedResultType.Error);
+            module.OnFinish(result, null);
+
+            // Check if sync was not recorded
+            cmd.CommandText = "SELECT COUNT(*) FROM \"Operation\" WHERE \"Description\" = 'Rsync 0'";
+            var count = (long)cmd.ExecuteScalar();
+            Assert.AreEqual(0, count);
+        }
+    }
+
+    /// <summary>
+    /// Simple implementation of IBasicResults for testing.
+    /// </summary>
+    public class TestBasicResults : IBasicResults
+    {
+        public TestBasicResults(ParsedResultType parsedResult)
+        {
+            ParsedResult = parsedResult;
+        }
+
+        public DateTime BeginTime => DateTime.UtcNow;
+        public DateTime EndTime => DateTime.UtcNow;
+        public TimeSpan Duration => TimeSpan.Zero;
+        public IEnumerable<string> Errors => new string[0];
+        public IEnumerable<string> Warnings => new string[0];
+        public IEnumerable<string> Messages => new string[0];
+        public ParsedResultType ParsedResult { get; }
+        public bool Interrupted => false;
+    }
+}
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