Error uploading file pdf

You made some misconfiguration in upload method code,

1. `upload_url` not any config type in upload library.
   
2. `max_size` value by default in KB not need to add in value
   
3. better to use more Upload library functions.
   
4. you should create ./upload directory on project root folder and use `FCPATH` constant to go folder location.
   

see below correct sample code

PHP Code:

function uploadFile() {
    $config['upload_path'] = FCPATH . "/upload/";
    $config['allowed_types'] = "pdf";
    $config['overwrite'] = TRUE;
    $config['max_size'] = "1000";
    $config['file_name'] = "namearchivo";
    $this->load->library('upload', $config);

    if ($this->upload->do_upload()) {
        $file_data = $this->upload->data();
        $file_name = $file_data['file_name'];
        redirect($urlAnterior);
    } else {
        echo $this->upload->display_errors('<p>', '</p>');
        //redirect($urlAnterior);
    }
} 


Probably solution would be work for you  

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