diff --git a/Arrowgene.Ddon.Database/Sql/Core/Migration/00000026_TaskSchedulerMigration.cs b/Arrowgene.Ddon.Database/Sql/Core/Migration/00000026_TaskSchedulerMigration.cs
deleted file mode 100644
index d99366b89..000000000
--- a/Arrowgene.Ddon.Database/Sql/Core/Migration/00000026_TaskSchedulerMigration.cs
+++ /dev/null
@@ -1,25 +0,0 @@
-using System.Data.Common;
-
-namespace Arrowgene.Ddon.Database.Sql.Core.Migration
-{
-    public class TaskSchedulerMigration : IMigrationStrategy
-    {
-        public uint From => 26;
-        public uint To => 27;
-
-        private readonly DatabaseSetting DatabaseSetting;
-
-        public TaskSchedulerMigration(DatabaseSetting databaseSetting)
-        {
-            DatabaseSetting = databaseSetting;
-        }
-
-        public bool Migrate(IDatabase db, DbConnection conn)
-        {
-            string adaptedSchema = DdonDatabaseBuilder.GetAdaptedSchema(DatabaseSetting, "Script/migration_scheduling.sql");
-            db.Execute(conn, adaptedSchema);
-            return true;
-        }
-    }
-}
-