login page doesn't work only on aws

i recently push my rails4 app on aws. The landing page work (some others too) but the login and subscribe page don't. and they do on localhost.

I have "we're sry blalbla check log" the probleme is i have no information on my log file

just this line :

Started GET "/login" for 93.26.170.84 at 2015-08-09 15:10:43 +0000

for the request and nothing else.

I am on development environment.

What would you do to find what the problem is ?

thx for your time !