Cannot modify header information – headers already sent by

Warning: Cannot modify header information – headers already sent by (output started at /home/affiliat/public_html/wp-config.php:1) in /home/affiliat/public_html/wp-includes/pluggable.php on line 881

unable to login wp-admin panel

here is my wp-config.php

<?php
define('DB_NAME', 'affiliat_wrdp1');

/** MySQL database username */
define('DB_USER', 'affiliat_wrdp1');

/** MySQL database password */
define('DB_PASSWORD', 'MODREMOVED');

/** MySQL hostname */
define('DB_HOST', 'localhost');

/** Database Charset to use in creating database tables. */
define('DB_CHARSET', 'utf8');

/** The Database Collate type. Don't change this if in doubt. */
define('DB_COLLATE', '');

/**#@+
 * Authentication Unique Keys and Salts.
 *
 * Change these to different unique phrases!
 * You can generate these using the {@link https://api.www.ads-software.com/secret-key/1.1/salt/ www.ads-software.com secret-key service}
 * You can change these at any point in time to invalidate all existing cookies. This will force all users to have to log in again.
 *
 * @since 2.6.0
 */
define('AUTH_KEY',         'MODREMOVED');
define('SECURE_AUTH_KEY',  'MODREMOVED');
define('LOGGED_IN_KEY',    'MODREMOVED');
MOD: KEYS REMOVED FOR SECURITY );

/**#@-*/

/**
 * WordPress Database Table prefix.
 *
 * You can have multiple installations in one database if you give each a unique
 * prefix. Only numbers, letters, and underscores please!
 */
$table_prefix  = 'wp_';

/**
 * WordPress Localized Language, defaults to English.
 *
 * Change this to localize WordPress. A corresponding MO file for the chosen
 * language must be installed to wp-content/languages. For example, install
 * de_DE.mo to wp-content/languages and set WPLANG to 'de_DE' to enable German
 * language support.
 */
define('WPLANG', '');

/**
 * For developers: WordPress debugging mode.
 *
 * Change this to true to enable the display of notices during development.
 * It is strongly recommended that plugin and theme developers use WP_DEBUG
 * in their development environments.
 */
define('WP_DEBUG', false);

/* That's all, stop editing! Happy blogging. */

/** Absolute path to the WordPress directory. */
if ( !defined('ABSPATH') )
    define('ABSPATH', dirname(__FILE__) . '/');

/** Sets up WordPress vars and included files. */
require_once(ABSPATH . 'wp-settings.php');

[mod: never post any passwords or security codes]