diff --git a/MareSynchronos/PlayerData/Handlers/PairHandler.cs b/MareSynchronos/PlayerData/Handlers/PairHandler.cs
index f222b93..8a346e2 100644
--- a/MareSynchronos/PlayerData/Handlers/PairHandler.cs
+++ b/MareSynchronos/PlayerData/Handlers/PairHandler.cs
@@ -580,7 +580,7 @@ public sealed class PairHandler : DisposableMediatorSubscriberBase
     private List<FileReplacementData> TryCalculateModdedDictionary(Guid applicationBase, CharacterData charaData, out Dictionary<string, string> moddedDictionary, CancellationToken token)
     {
         Stopwatch st = Stopwatch.StartNew();
-        List<FileReplacementData> missingFiles = new();
+        ConcurrentBag<FileReplacementData> missingFiles = new();
         moddedDictionary = new Dictionary<string, string>(StringComparer.Ordinal);
         ConcurrentDictionary<string, string> outputDict = new(StringComparer.Ordinal);
         bool hasMigrationChanges = false;
@@ -634,6 +634,6 @@ public sealed class PairHandler : DisposableMediatorSubscriberBase
         if (hasMigrationChanges) _fileDbManager.WriteOutFullCsv();
         st.Stop();
         Logger.LogDebug("[BASE-{appBase}] ModdedPaths calculated in {time}ms, missing files: {count}, total files: {total}", applicationBase, st.ElapsedMilliseconds, missingFiles.Count, moddedDictionary.Keys.Count);
-        return missingFiles;
+        return missingFiles.ToList();
     }
 }
\ No newline at end of file
diff --git a/MareSynchronos/WebAPI/Files/FileDownloadManager.cs b/MareSynchronos/WebAPI/Files/FileDownloadManager.cs
index d1d29cf..ab72fdc 100644
--- a/MareSynchronos/WebAPI/Files/FileDownloadManager.cs
+++ b/MareSynchronos/WebAPI/Files/FileDownloadManager.cs
@@ -188,7 +188,7 @@ public partial class FileDownloadManager : DisposableMediatorSubscriberBase
         Logger.LogDebug("Download start: {id}", gameObjectHandler.Name);
 
         List<DownloadFileDto> downloadFileInfoFromService = new();
-        downloadFileInfoFromService.AddRange(await FilesGetSizes(fileReplacement.Select(f => f.Hash).ToList(), ct).ConfigureAwait(false));
+        downloadFileInfoFromService.AddRange(await FilesGetSizes(fileReplacement.Select(f => f.Hash).Distinct(StringComparer.Ordinal).ToList(), ct).ConfigureAwait(false));
 
         Logger.LogDebug("Files with size 0 or less: {files}", string.Join(", ", downloadFileInfoFromService.Where(f => f.Size <= 0).Select(f => f.Hash)));