IE11 has some issues with vB5 as it stands now due to bad browser detection. These changes should address the issues at hand until the software is patched.

In core/includes/functions.php find:


PHP- Kodu:
// detect macintosh 

Add above:


PHP- Kodu:
// Detect Modern IE11+
 
        if (strpos($useragent, 'trident') !== false AND !$is['opera'] AND !$is['ie'])
 
        {
 
            preg_match('#rv:([0-9\.-]+)#', $useragent, $regs);
 
            $is['ie'] = $regs[1];
 
 
 
        } 

Next, find:

PHP- Kodu:
if (strpos($useragent, 'gecko') !== false AND !$is['safari'] AND !$is['konqueror']) 

And replace it with

PHP- Kodu:
if (strpos($useragent, 'gecko') !== false AND !$is['safari'] AND !$is['konqueror'] AND !$is['ie']) 
Next, we have one more change to make:

In /includes/vb5/frontend/controller.php Find


PHP- Kodu:
  if (isset($_SERVER['HTTP_USER_AGENT']) &&
            (strpos($_SERVER['HTTP_USER_AGENT'], 'MSIE') !== false))
        {
            header('Content-type: text/plain; charset=UTF-8');
        } 
Add after


PHP- Kodu:
  // IE11+ detection, MS changed the UA
        elseif (isset($_SERVER['HTTP_USER_AGENT']) &&
            (strpos($_SERVER['HTTP_USER_AGENT'], 'Trident') !== false))
        {
 
            header('Content-type: text/plain; charset=UTF-8');        
        }