Session doesn't end when browser window is closed

Oh ya one other thing make sure you are setting your validation messages using CodeIgniter Session Flash Data
http://www.codeigniter.com/user_guide/li...#flashdata

If you are seeing your validation message(s) every time you view the page (if I read that right) then it sounds like your are using CodeIgniter userdata sessions

"CodeIgniter supports “flashdata”, or session data that will only be available for the next request, and is then automatically cleared."

Don Myers

https://github.com/ProjectOrangeBox / https://github.com/dmyers2004