neuro75

I didn’t plan to use any additional plugins for login. I want to use the standard features W3all.
Just when I was off earlier I referred to the lines in the file page-board.php, by clicking on phpBB login, I opened inside the frame standard phpBB login page, put the name and password, and all work correctly. It suits me fine. When the user logs into phpBB, simultaneously automatically and login to WP.
As in the default configuration, login in phpBB is not working, and only works with the disconnected lines in phpBB, I did not know that the entrance is scheduled in a modal window.
I was quite satisfied with the standard login in phpBB in a frame. I also want to put on the page WP button to the user profile, but as a profile to use page of profile phpBB.
How do I make it so that when I press the phpBB login, in a frame opened standard login page of phpBB?
And what is the link I must write to the button in WP to opened phpBB profile page in a frame?

My WP stand up into root of mysite.com.
My default .htaccess in this folder is

# BEGIN WordPress

# END WordPress

In the previous discussion you recomended replace its content on:

# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /your_path_to_wordpress/
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /your_path_to_wordpress/index.php [L]
</IfModule>

# END WordPress

I paste:

# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>

# END WordPress

Whether I pointed the path in the fourth and eighth line?

After this I recompile page-board.php (set is default).

Now аll the links except for login/logout still work correctly.
When I click on login/logout, for a split second, the correct image appears in the frame (fields of a login and password) then the site goes to home page (out of iframe to the main page WP). In the address bar of the browser when it is written http://mysite.com/board/#w3allopenModal
But 404 error is now no more!
What do I do next?

No. I always have error 404

Yes, now i have correct redirection in case the user login and logout.
My .htaccess in WP root contains only the following lines:

# BEGIN WordPress

# END WordPress

In fact, it is empty.
.htaccess in phpBB root (/forum) contains (сommented lines I removed):

<IfModule mod_rewrite.c>
RewriteEngine on

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ app.php [QSA,L]

</IfModule>
<IfModule mod_version.c>
	<IfVersion < 2.4>
		<Files "config.php">
			Order Allow,Deny
			Deny from All
		</Files>
		<Files "common.php">
			Order Allow,Deny
			Deny from All
		</Files>
	</IfVersion>
	<IfVersion >= 2.4>
		<Files "config.php">
			Require all denied
		</Files>
		<Files "common.php">
			Require all denied
		</Files>
	</IfVersion>
</IfModule>
<IfModule !mod_version.c>
	<IfModule !mod_authz_core.c>
		<Files "config.php">
			Order Allow,Deny
			Deny from All
		</Files>
		<Files "common.php">
			Order Allow,Deny
			Deny from All
		</Files>
	</IfModule>
	<IfModule mod_authz_core.c>
		<Files "config.php">
			Require all denied
		</Files>
		<Files "common.php">
			Require all denied
		</Files>
	</IfModule>
</IfModule>

I do not understand the question.
Site located at http://clubkavkaz.ru and work. Link http://clubkavkaz.ru/board/ and http://clubkavkaz.ru/board/#w3allopenModal generated if i press “login” or “logout” into phpBB and not work (page 404).
In other cases, the generated links look like http://clubkavkaz.ru/index.php/board/?viewforum=… and work.
How can I do so that worked “login” and “logout” into phpBB?