I have a forum installed with my Wordpress site. My pagination does not work and redirects pages 2,3, or more to baseurl when they are on homepage. Here are the settings:

Forum baseurl: 
Permalink structure: /%category%/%postname%/

Question link: /   (Works)
Author link: /             (Works)
Category link: /              (Works)
CategoryPosts page2: / (Works)
Tag Posts page2: / (Works) 

HomePage questions Pagination looks like this,

/?page=2

and redirects back to

For pagination on category and tag pages, it looks correct (/ & /)

Here is the .htaccess:

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