BuddyPress.org

Hello,
I’m writing a topic because I have a problem. Whatever the status of the member, writing to post a comment and to write a message on our own page or on a group page does not work.
I don’t really understand why, because the first time I tried to post something it worked but other time it was written “Are you sure?” with a link which ask me to retry.

I’ve updated the website in 3.9.1 in order to install BuddyPress. I’ve tried to desactivate some plugin. I’ve desactivated BuddyPress uninstalled it, deleted the database.
But nothing’s changed

Do you have any idea to answer to my issue?

PS : Sorry for my bad English :/