A function was called incorrectly.
WHAT IT MEANS
The code called a function without supplying everything it requires.
THE COMMON CAUSES
A plugin or theme calling a function whose signature changed in an update Custom code written against an older version of something Two components disagreeing about a shared function
AFTER AN UPDATE
The most common context. Something updated, and another component is calling it the old way.
Check whether the calling component has an update available.
If it does not, and the developer is unresponsive, that component may be abandoned.
THE ERROR NAMES THE FUNCTION AND FILE
Both the function that was called and the file that called it. The second identifies the responsible component.
THE IMMEDIATE FIX
Disable the component making the incorrect call, by renaming its directory in File Manager.
That restores the site while you decide what to do.
FOR CUSTOM CODE
Check the current signature of the function you are calling. Frameworks and libraries change these between major versions.
IF IT APPEARED AFTER A PHP VERSION CHANGE
PHP became stricter about this. Older code that worked may now fail.
