     }
     if ( filename.length() > 30 )
     {
-      Serial.println( "Upload filename too long!" );
-      return;
+      return server.send( 400, textPlainHeader, "Upload filename too long!" );
     }
     if ( upload.status == UPLOAD_FILE_START )
     {

  {
    if ( !server.authenticate( www_username, www_password ) )
    {
      server.requestAuthentication();
      return;
    }
    else
    {

  {
    if ( !server.authenticate( www_username, www_password ) )
    {
      return server.requestAuthentication();
    }
    else
    {
