About <<Agile web development with rails>>

there is a example application “depot” in the book,
when you login: http://localhost/login
the login form shows,then you enter an error user name or bad pass
word,there will show an flash notice “Invalid user/password
combination” on top of the login form, it’s right,
but when you type the url:http://localhost/store,something went
wrong,the flash note is still showing on top of the category list,
anybody can tell me why?