diff --git a/Hayden.WebServer/Data/HaydenDataProvider.cs b/Hayden.WebServer/Data/HaydenDataProvider.cs
index 78a5bac..ac6d8e3 100644
--- a/Hayden.WebServer/Data/HaydenDataProvider.cs
+++ b/Hayden.WebServer/Data/HaydenDataProvider.cs
@@ -338,7 +338,7 @@ public async Task<bool> DeletePost(ushort boardId, ulong postId, bool banImages)
 					var fullFilename = Common.CalculateFilename(config.Value.Data.FileLocation, board.ShortName, Common.MediaType.Image,
 						file.Sha256Hash, file.Extension);
 					var thumbFilename = Common.CalculateFilename(config.Value.Data.FileLocation, board.ShortName, Common.MediaType.Thumbnail,
-						file.Sha256Hash, file.Extension);
+						file.Sha256Hash, "jpg");
 
 					System.IO.File.Delete(fullFilename);
 					System.IO.File.Delete(thumbFilename);
@@ -383,4 +383,4 @@ public static (string imageUrl, string thumbnailUrl) GenerateUrls(DBFile file, s
 			return (imageUrl, thumbUrl);
 		}
 	}
-}
\ No newline at end of file
+}