How to Fix Codeigniter File Uploading Class Fails

Yes it does, and it throws this error "The filetype you are attempting to upload is not allowed." even though you have specified your file in the class's "allowed_types" property.

Solution:
1.) Overwrite the Upload class by creating a new My_Upload.php file in your application/libraries directory

2.) Paste the following code, notice I have added the "if($this->is_image())" condition, since the code should only check the image size if the filetype is image.

class My_Upload extends CI_Upload {
 function is_allowed_filetype()
 {
  if (count($this->allowed_types) == 0 OR ! is_array($this->allowed_types))
  { 
   $this->set_error('upload_no_file_types');
   return FALSE;
  }

  $image_types = array('gif', 'jpg', 'jpeg', 'png', 'jpe');

  foreach ($this->allowed_types as $val)
  {
   $mime = $this->mimes_types(strtolower($val));

   // Images get some additional checks
   if (in_array($val, $image_types))
   { 
    if($this->is_image()) {
     if (getimagesize($this->file_temp) === FALSE)
     {
      return FALSE;
     }
    }
   }
   
   if (is_array($mime))
   {
    if (in_array($this->file_type, $mime, TRUE))
    {
     return TRUE;
    }
   }
   else
   {
    if ($mime == $this->file_type)
    { 
     return TRUE;
    } 
   }  
  }
  return FALSE;
 }
}