diff --git a/Duplicati/Library/Main/RSyncDir.cs b/Duplicati/Library/Main/RSyncDir.cs
index aa5628f34..eab7ddae8 100644
--- a/Duplicati/Library/Main/RSyncDir.cs
+++ b/Duplicati/Library/Main/RSyncDir.cs
@@ -1182,14 +1182,21 @@ namespace Duplicati.Library.Main.RSync
         /// <returns>A full path, based on the relative path</returns>
         private static string GetFullPathFromRelname(string[] sourcefolders, string relpath)
         {
-            if (sourcefolders.Length == 1)
-                return System.IO.Path.Combine(sourcefolders[0], relpath);
-            else
+            try
             {
-                int ix = relpath.IndexOf(System.IO.Path.DirectorySeparatorChar);
-                //In some versions, Duplicati incorrectly writes the folder name without a trailing slash
-                int pos = ix < 0 ? int.Parse(relpath) : int.Parse(relpath.Substring(0, ix));
-                return System.IO.Path.Combine(sourcefolders[Math.Min(sourcefolders.Length - 1, pos)], relpath.Substring(ix + 1));
+                if (sourcefolders.Length == 1)
+                    return System.IO.Path.Combine(sourcefolders[0], relpath);
+                else
+                {
+                    int ix = relpath.IndexOf(System.IO.Path.DirectorySeparatorChar);
+                    //In some versions, Duplicati incorrectly writes the folder name without a trailing slash
+                    int pos = ix < 0 ? int.Parse(relpath) : int.Parse(relpath.Substring(0, ix));
+                    return System.IO.Path.Combine(sourcefolders[Math.Min(sourcefolders.Length - 1, pos)], relpath.Substring(ix + 1));
+                }
+            }
+            catch (Exception ex)
+            {
+                throw new ArgumentException(string.Format(Strings.RSyncDir.InvalidRelFilenameError, relpath, string.Join(Environment.NewLine, sourcefolders), ex.Message) , ex);
             }
         }
 
diff --git a/Duplicati/Library/Main/Strings/RSyncDir.Designer.cs b/Duplicati/Library/Main/Strings/RSyncDir.Designer.cs
index 03621e2f4..c7a7142b2 100644
--- a/Duplicati/Library/Main/Strings/RSyncDir.Designer.cs
+++ b/Duplicati/Library/Main/Strings/RSyncDir.Designer.cs
@@ -1,7 +1,7 @@
 //------------------------------------------------------------------------------
 // <auto-generated>
 //     This code was generated by a tool.
-//     Runtime Version:4.0.30319.237
+//     Runtime Version:4.0.30319.544
 //
 //     Changes to this file may cause incorrect behavior and will be lost if
 //     the code is regenerated.
@@ -207,6 +207,15 @@ namespace Duplicati.Library.Main.Strings {
             }
         }
         
+        /// <summary>
+        ///   Looks up a localized string similar to Invalid filename detected: {0}, source folders: {1}, error message: {2}.
+        /// </summary>
+        internal static string InvalidRelFilenameError {
+            get {
+                return ResourceManager.GetString("InvalidRelFilenameError", resourceCulture);
+            }
+        }
+        
         /// <summary>
         ///   Looks up a localized string similar to The timestamp information for file {0} could not be read: {1}.
         /// </summary>
@@ -288,6 +297,15 @@ namespace Duplicati.Library.Main.Strings {
             }
         }
         
+        /// <summary>
+        ///   Looks up a localized string similar to The symlink information for {0} could not be read: {1}.
+        /// </summary>
+        internal static string SymlinkReadError {
+            get {
+                return ResourceManager.GetString("SymlinkReadError", resourceCulture);
+            }
+        }
+        
         /// <summary>
         ///   Looks up a localized string similar to Failed to dispose USN helper: {0}.
         /// </summary>
@@ -332,14 +350,5 @@ namespace Duplicati.Library.Main.Strings {
                 return ResourceManager.GetString("UsnNumberingFaultWarning", resourceCulture);
             }
         }
-
-        /// <summary>
-        ///   Looks up a localized string similar to The symlink information for {0} could not be read: {1}.
-        /// </summary>
-        internal static string SymlinkReadError {
-            get {
-                return ResourceManager.GetString("SymlinkReadError", resourceCulture);
-            }
-        }
-}
+    }
 }
diff --git a/Duplicati/Library/Main/Strings/RSyncDir.resx b/Duplicati/Library/Main/Strings/RSyncDir.resx
index a1392cb09..bd02454ee 100644
--- a/Duplicati/Library/Main/Strings/RSyncDir.resx
+++ b/Duplicati/Library/Main/Strings/RSyncDir.resx
@@ -213,4 +213,7 @@ Error message: {1}</value>
   <data name="SymlinkReadError" xml:space="preserve">
     <value>The symlink information for {0} could not be read: {1}</value>
   </data>
+  <data name="InvalidRelFilenameError" xml:space="preserve">
+    <value>Invalid filename detected: {0}, source folders: {1}, error message: {2}</value>
+  </data>
 </root>
\ No newline at end of file