Site Logout Error

When I logout of my website I get this error: Warning: smfapi_loadDatabase(/home/main-doimain-location/public_html/domain.name/OLD/forum/Sources/Subs-Db-mysql.php): failed to open stream: No such file or directory in /home/destination/public_html/domain.name/forum/smf_2_api.php on line 0 Fatal error: smfapi_loadDatabase(): Failed opening required '/home/main-domain-location/public_html/domain.name/OLD/forum/Sources/Subs-Db-mysql.php' (include_path='.:/opt/cpanel/ea-php72/root/usr/share/pear') in /home/main-domain-location/public_html/domain.name/forum/smf_2_api.php on line 0 How to fix?