Session userdata disappearing after session updates

[eluser]StevenW721[/eluser]
What are your other session preferences set to?

I think I'm getting a similar issue but it's only happening on a clients computer running IE6. I can't seem to replicate the issue from here even with IE6. Could it be anything to do with their network?

Here's our session preferences...

Code:

$config['sess_cookie_name']       = 'int_session';
$config['sess_expiration']        = 28800; //8 hours
$config['sess_encrypt_cookie']    = TRUE;
$config['sess_use_database']      = TRUE;
$config['sess_table_name']        = 'int_sessions';
$config['sess_match_ip']          = TRUE;
$config['sess_match_useragent']   = TRUE;
$config['sess_time_to_update']    = 300;

Originally we had the sess_time_to_update set to 30 and the sess_expiration set to 2 hours but after hearing they were having issues I reverted back to the default 300 for the update and bumped the expiration to 8 hours to see what that did. Still there's an issue with them losing the session data.