diff --git a/test/plugin/test_in_tail.rb b/test/plugin/test_in_tail.rb
index 6fa6ccfc59..cf7610eb5b 100644
--- a/test/plugin/test_in_tail.rb
+++ b/test/plugin/test_in_tail.rb
@@ -31,60 +31,11 @@ def cleanup_directory(path)
       return
     end
 
-    if Fluent.windows?
-      Dir.glob("*", base: path).each do |name|
-        begin
-          cleanup_file(File.join(path, name))
-        rescue
-          # expect test driver block release already owned file handle.
-        end
-      end
-    else
-      begin
-        FileUtils.rm_f(path, secure:true)
-      rescue ArgumentError
-        FileUtils.rm_f(path) # For Ruby 2.6 or before.
-      end
-      if File.exist?(path)
-        FileUtils.remove_entry_secure(path, true)
-      end
-    end
-    FileUtils.mkdir_p(path)
+    FileUtils.remove_entry_secure(path, true)
   end
 
   def cleanup_file(path)
-    if Fluent.windows?
-      # On Windows, when the file or directory is removed and created
-      # frequently, there is a case that creating file or directory will
-      # fail. This situation is caused by pending file or directory
-      # deletion which is mentioned on win32 API document [1]
-      # As a workaround, execute rename and remove method.
-      #
-      # [1] https://docs.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-createfilea#files
-      #
-      file = File.join(Dir.tmpdir, SecureRandom.hex(10))
-      begin
-        FileUtils.mv(path, file)
-        FileUtils.rm_rf(file, secure: true)
-      rescue ArgumentError
-        FileUtils.rm_rf(file) # For Ruby 2.6 or before.
-      end
-      if File.exist?(file)
-        # ensure files are closed for Windows, on which deleted files
-        # are still visible from filesystem
-        GC.start(full_mark: true, immediate_mark: true, immediate_sweep: true)
-        FileUtils.remove_entry_secure(file, true)
-      end
-    else
-      begin
-        FileUtils.rm_f(path, secure: true)
-      rescue ArgumentError
-        FileUtils.rm_f(path) # For Ruby 2.6 or before.
-      end
-      if File.exist?(path)
-        FileUtils.remove_entry_secure(path, true)
-      end
-    end
+    FileUtils.remove_entry_secure(path, true)
   end
 
   def create_target_info(path)