Sometimes you may face the following error for a wordpress website.
Fatal error: Class ‘NOOP_Translations’ not found in wp-includes/l10n.php
This issue can be resolved by simply deleting/renaming current translations.php file in wp-includes/pomo folder and reupload it from current version of the wordpress.
# mv wp-includes/pomo/translations.php wp-includes/pomo/translations.php.bk
Download the wordpress installer on local PC, extract it and copy/upload the file from wp-includes/pomo to wp-includes/pomo folder on your server.