diff --git a/src/ClaudeDo.Ui/ViewModels/Islands/DetailsIslandViewModel.cs b/src/ClaudeDo.Ui/ViewModels/Islands/DetailsIslandViewModel.cs
index 64f87d60..d7a1b8f0 100644
--- a/src/ClaudeDo.Ui/ViewModels/Islands/DetailsIslandViewModel.cs
+++ b/src/ClaudeDo.Ui/ViewModels/Islands/DetailsIslandViewModel.cs
@@ -1099,7 +1099,8 @@ public sealed partial class DetailsIslandViewModel : ViewModelBase, IDisposable
             }
             catch (Exception ex)
             {
-                failures.Add($"{fileName}: {ex.Message}");
+                // Keep the exception type in the message so an intermittent failure is analyzable.
+                failures.Add($"{fileName}: {ex.GetType().Name}: {ex.Message}");
             }
         }
 
diff --git a/src/ClaudeDo.Ui/Views/Islands/DetailsIslandView.axaml.cs b/src/ClaudeDo.Ui/Views/Islands/DetailsIslandView.axaml.cs
index decd3fa2..52f95286 100644
--- a/src/ClaudeDo.Ui/Views/Islands/DetailsIslandView.axaml.cs
+++ b/src/ClaudeDo.Ui/Views/Islands/DetailsIslandView.axaml.cs
@@ -81,14 +81,28 @@ public partial class DetailsIslandView : UserControl
         if (items is null) return;
 
         var files = new List<(string FileName, System.IO.Stream Content)>();
-        foreach (var item in items)
+        try
         {
-            if (item is IStorageFile sf)
+            foreach (var item in items)
             {
-                var stream = await sf.OpenReadAsync();
-                files.Add((sf.Name, stream));
+                if (item is IStorageFile sf)
+                {
+                    var stream = await sf.OpenReadAsync();
+                    files.Add((sf.Name, stream));
+                }
             }
         }
+        catch (Exception ex)
+        {
+            // Opening the dropped stream can fail (shell IO, file lock) before AddFilesAsync
+            // ever runs; surface it with the exception type so the next occurrence is analyzable
+            // instead of vanishing as an unobserved async-void fault.
+            _vm.DropStatus = string.Format(
+                ClaudeDo.Ui.Localization.Loc.T("details.attachments.dropReadError"),
+                $"{ex.GetType().Name}: {ex.Message}");
+            foreach (var (_, s) in files) await s.DisposeAsync();
+            return;
+        }
 
         if (files.Count == 0) return;