www programming

Gilles Villeneuve, jeez, that was a while ago

Great, thanks, keep me posted!

after all afternoon, i've return over the pc, so i've open your site on fly.
I result correctly logged in, and no problem have come out.

So another thing that may you have to note, is this important one (this also explain to me why you was thinking that the error was due to phpBB):

if you login in phpBB via ssl/https: than after logged, you point instead to: so http, not https,
you'll see that you result logged out.
repoint to https: you'll result logged in other time correctly.
Cookie, as normal it need to be, are not recognized if released as https and you point to phpBB as http.

It clear now why the behavior. You simply, wrongly, access phpBB via http, and not https, and maybe you have links that point to forum via http, not https. The worst, is that maybe an user login while http: so will be never recognized in wp side, as on wp it is forced to be https (but cookie was released as http).

You see in WP side, that if you point to you're correctly forced to https:
this you need to do also in phpBB, force to redirect any http request, to an https request.

The same behavior you can experience here at axew3.com (http/https) because i've not setup nothing to fix it here via htaccess.
And this is your problem. Solution:
force phpBB to be accessed only via https, that mean any request to http url, will be rewrite to be https.

This will be added as hint on help sticky posts.

I see! Thank you. I've added this to phpbb .htaccess:
As far as I can see, it's not possible to access our forum through http anymore. Hope this will solve the problem.

this is it!
if now you point to http url on your phpBB and you'll be rewrite to https, it is ok ... http://httpd.apache.org/docs/2.2/mod/mod_rewrite.html
OR with examples:
http://www.askapache.com/htaccess/ssl-e ... p-to-https