still losing session userdata across a redirect

I have been battling this problem for a few weeks. My poor debugging choices introduced some other problems but I am back to my session problem. I found this post which shows that others have had the same problem. https://stackoverflow.com/questions/1206...odeigniter

I tried all the advice but it still doesn't work. Here is my config file:
$config['sess_driver'] = 'files';
$config['sess_cookie_name'] = 'ci_session';
$config['sess_expiration'] = 7200;
$config['sess_expiration'] = 0;
$config['sess_save_path'] = 'c:\xampp\htdocs\sub_crud\system\libraries\session';
$config['sess_match_ip'] = FALSE;
$config['sess_time_to_update'] = 300;
$config['sess_regenerate_destroy'] = FALSE;

I am considering trying either a flash session to move the one userdata variable I need, or else using database instead of files. Anyone have any other ideas?