I discover another problem, when the Easydiscuss module "Recent Discussions" is on Easyblog page, i have blank page.
It's make that only with easyblog page, no problem with categories.

Now i just desactivate Easydiscuss module "Recent Discussions" in some place and it's ok.

And i find another problem, when i post in easydiscuss and submit i have blank page and when i return on forum, have duplicate post.