diff --git a/back/src/Kyoo.Abstractions/Controllers/IThumbnailsManager.cs b/back/src/Kyoo.Abstractions/Controllers/IThumbnailsManager.cs
index 810998d8..d3cc15b5 100644
--- a/back/src/Kyoo.Abstractions/Controllers/IThumbnailsManager.cs
+++ b/back/src/Kyoo.Abstractions/Controllers/IThumbnailsManager.cs
@@ -19,8 +19,6 @@
 using System.Threading.Tasks;
 using Kyoo.Abstractions.Models;
 
-#nullable enable
-
 namespace Kyoo.Abstractions.Controllers
 {
 	/// <summary>
diff --git a/back/src/Kyoo.Core/Controllers/ThumbnailsManager.cs b/back/src/Kyoo.Core/Controllers/ThumbnailsManager.cs
index 8a0697d4..04db1a1f 100644
--- a/back/src/Kyoo.Core/Controllers/ThumbnailsManager.cs
+++ b/back/src/Kyoo.Core/Controllers/ThumbnailsManager.cs
@@ -140,7 +140,7 @@ namespace Kyoo.Core.Controllers
 			{
 				lock (_downloading)
 				{
-					if (File.Exists(posterPath) || _downloading.ContainsKey(posterPath))
+					if (_downloading.ContainsKey(posterPath))
 					{
 						duplicated = true;
 						sync = _downloading.GetValueOrDefault(posterPath);
@@ -154,7 +154,8 @@ namespace Kyoo.Core.Controllers
 				if (duplicated)
 				{
 					object? dup = sync != null ? await sync.Task : null;
-					throw new DuplicatedItemException(dup);
+					if (dup != null)
+						throw new DuplicatedItemException(dup);
 				}
 
 				await _DownloadImage(