There should be a "profile.php" in the main folder of the forum. Open it with a text editor and look for the following data:
if ($form['disp_topics'] != '' && intval($form['disp_topics']) < 3) $form['disp_topics'] = 3;
if ($form['disp_topics'] != '' && intval($form['disp_topics']) > 75) $form['disp_topics'] = 75;
if ($form['disp_posts'] != '' && intval($form['disp_posts']) < 3) $form['disp_posts'] = 3;
if ($form['disp_posts'] != '' && intval($form['disp_posts']) > 75) $form['disp_posts'] = 75;
Change it to:
if ($form['disp_topics'] != '' && intval($form['disp_topics']) < 3) $form['disp_topics'] = 3;
//if ($form['disp_topics'] != '' && intval($form['disp_topics']) > 75) $form['disp_topics'] = 75;
if ($form['disp_posts'] != '' && intval($form['disp_posts']) < 3) $form['disp_posts'] = 3;
//if ($form['disp_posts'] != '' && intval($form['disp_posts']) > 75) $form['disp_posts'] = 75;
Save the file.
This will increase the limit to 999.
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