SQL-DATABASE ERROR

Database error in WoltLab Burning Board (2.3.6): Link-ID == false, connect failed
mysql error: No such file or directory
mysql error number: 2002
mysql version: unknown
php version: 5.6.40-nmm8
Date: 16.05.2024 @ 05:30
Script: /xforum/calendar.php?sid=41b3e05518676c922955bf381cfdb32e
Referer: