The create account button not desplayed

I set up a new Mattermost 3.4.0 Team Edition,
but the create account button doesn't display on the login page.
Just the login forms display on it.

capture.PNG1101x819 31.9 KB

Enable Account Creation is "true".
I can make user accounts by CLI but I want my team members to make their own account.

Could you tell me how to solve this?
Thank you.

I'm using
OS : CentOS 7.2 on Windows Server with Vagrant.
DB : msql 5.7.
Client : Firefox, Chrome, Mattermost Desktop