https://wpforo.com/wp-content/uploads/2017/02/2017-02-11_1948.png

Also please deactivate other plugins too and delete cache + do Ctrl+F5 on forum pages before checking.

It means the conflict is with Yoast. Try to deactivate it and test.

Tested by deactivating both yoast and AIO. No titles were generated. 

The other issue is that Page Titles are not being generated for Topics. All topics have the default page title of: Deck Stain Forum | Best Deck Stain Review Ratings

It comes from SEO plugin, if you use All In One plugin please change it to Yoast SEO. We're currently working to fix SEO plugin conflicts. They conflicts with built-in wpForo SEO, but Yoast SEO.

FYI, I tested this be deactivating AIO and activating Yoast. The Page titles were still not being generated. 

Please contact to the developer who did this migration, ask them to re-create Full Text Index. They'll do that very easy. You can't do that. You should change "created" and "modified" fields default value to "CURRENT_DATETIME", then delete all Full Text indexes and then execute the SQL I've mentioned above.

Thanks I will contact them

SET SQL_MODE = "NO_AUTO_VALUE_ON_ZERO";
ALTER TABLE `wp_wpforo_posts` ADD FULLTEXT KEY `title` (`title`);
ALTER TABLE `wp_wpforo_posts` ADD FULLTEXT KEY `body` (`body`);
ALTER TABLE `wp_wpforo_posts` ADD FULLTEXT KEY `title_plus_body` (`title`,`body`);

PLEASE NOTE: It's correct to get  "# MySQL returned an empty result set (i.e. zero rows).", this SQL doesn't return any value, so message is correct. try the SQL again and if you got the same massage don't think it's an error.

The other issue is that Page Titles are not being generated for Topics. All topics have the default page title of: Deck Stain Forum | Best Deck Stain Review Ratings

It comes from SEO plugin, if you use All In One plugin please change it to Yoast SEO. We're currently working to fix SEO plugin conflicts. They conflicts with built-in wpForo SEO, but Yoast SEO.

https://www.deckstainhelp.com/community/

I am having another issue with the forum posts not generating Titles for the page that I posted earlier. Maybe this is related?