MyBB Community Forums

^ it happens - you can see many such stressing issues if you look around
this community OR any other software supporting community - fight / leave

that's true. also annoying if you cant access your ACP. You atleast have some control then.

The add_shutdown function is in inc/functions.php so if you don't have it, your inc/functions.php file is bad. Restoring a backup won't fix the file so the problem will persist.

I checked and turns out I don't have it. What can be done to fix this problem?

Upload the original inc/functions.php from the MyBB package.

Love it. Thx for the help.