Error map

DivisionByZeroError Fatal error: Uncaught DivisionByZeroError: Division by zero

PHP · layer 4, Application & API

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DivisionByZeroError — Fatal error: Uncaught DivisionByZeroError: Division by zero (PHP)DivisionByZ…Call to undefined function — PHP Fatal error: Uncaught Error: Call to undefined function (PHP)Call to undefined f…Call to member function on null — Fatal error: Uncaught Error: Call to a member function x() on null (PHP)Call to member func…ArgumentCountError — Fatal error: Uncaught ArgumentCountError: Too few arguments to function foo(), 1 passed and exactly 2 expected (PHP)ArgumentCountErrorCall to undefined function (WordPress) — WordPress: Fatal error: Uncaught Error: Call to undefined function wp_get_current_user() / add_action() / get_header() (WordPress)Call to undefined f…Cannot redeclare — Fatal error: Cannot redeclare function foo() (previously declared in …) (PHP)Cannot redeclareZeroDivisionError — ZeroDivisionError: division by zero (Python)ZeroDivisionErrorAllowed memory size exhausted — PHP Fatal error: Allowed memory size of X bytes exhausted (PHP)Allowed memory size…Plugin could not be activated because it triggered a fatal error — WordPress: Plugin could not be activated because it triggered a fatal error (WordPress)Plugin could not be…Division by zero — SQL Error: division by zero / Divide by zero error encountered (SQL)Division by zeroCannot use object as array — Fatal error: Uncaught Error: Cannot use object of type stdClass as array (PHP)Cannot use object a…500 — HTTP 500 Internal Server Error (HTTP)500Class not found — PHP Fatal error: Uncaught Error: Class "X" not found (PHP)Class not foundHeaders already sent — Warning: Cannot modify header information - headers already sent (PHP)Headers already sentNullReferenceException — System.NullReferenceException: Object reference not set to an instance of an object (.NET)NullReferenceExcept…Maximum execution time — PHP Fatal error: Maximum execution time of 30 seconds exceeded (PHP)Maximum execution t…Parse error — PHP Parse error: syntax error, unexpected … (PHP)Parse errorCritical error — WordPress: There Has Been a Critical Error on This Website (WordPress)Critical errorTypeError — Fatal error: Uncaught TypeError: foo(): Argument #1 ($x) must be of type int, string given (PHP)TypeErrormysqli_sql_exception — Fatal error: Uncaught mysqli_sql_exception (PHP)mysqli_sql_exceptionMaximum function nesting — Fatal error: Maximum function nesting level of '256' reached, aborting! (PHP)Maximum function ne…Installation failed: Could not create directory — WordPress: Installation failed: Could not create directory (plugin/theme install or update) (WordPress)Installation failed…Please enter your FTP credentials — To perform the requested action, WordPress needs to access your web server. Please enter your FTP credentials to proceed (WordPress)Please enter your F…failed to open stream — Warning: include(x.php): Failed to open stream: No such file or directory (PHP)failed to open stre…Uncaught Exception — Fatal error: Uncaught Exception: message in file.php:12 (PHP)Uncaught ExceptionReferenceError — ReferenceError: x is not defined (JavaScript)ReferenceErrorRangeError — RangeError: Maximum call stack size exceeded (JavaScript)RangeErrorKeyError — KeyError: 'x' (Python)KeyErrorOOMKilled — Kubernetes: OOMKilled (exit code 137) (Kubernetes)OOMKilled413 — HTTP 413 Content Too Large (Request Entity Too Large) (HTTP)413OutOfMemoryError — java.lang.OutOfMemoryError: Java heap space (Java)OutOfMemoryErrorDestination folder already exists — WordPress: Destination folder already exists. Plugin installation failed (WordPress)Destination folder …No valid plugins were found — The package could not be installed. No valid plugins were found (WordPress)No valid plugins we…requires at least PHP — WordPress: Your server is running PHP version 7.2 but WordPress 6.x requires at least 7.4 / This plugin requires a newer version of PHP (WordPress)requires at least P…TypeError: NoneType — TypeError: 'NoneType' object is not subscriptable (Python)TypeError: NoneTypeGROUP BY — Column must appear in the GROUP BY clause / isn't in GROUP BY (MySQL 1055 only_full_group_by) (SQL)GROUP BYClassCastException — java.lang.ClassCastException: class A cannot be cast to class B (Java)ClassCastExceptionArray to string conversion — Warning: Array to string conversion (PHP)Array to string con…Unsupported operand types — Fatal error: Uncaught TypeError: Unsupported operand types: string + int (PHP)Unsupported operand…

Directly related (10)

Call to undefined functionPHP

PHP Fatal error: Uncaught Error: Call to undefined function

PHP can’t find the function you called — usually a missing extension, missing include, or namespace issue.

Call to member function on nullPHP

Fatal error: Uncaught Error: Call to a member function x() on null

Code called a method on a variable that is null instead of an object.

ArgumentCountErrorPHP

Fatal error: Uncaught ArgumentCountError: Too few arguments to function foo(), 1 passed and exactly 2 expected

A function was called with fewer arguments than it requires.

Call to undefined function (WordPress)WordPress

WordPress: Fatal error: Uncaught Error: Call to undefined function wp_get_current_user() / add_action() / get_header()

Code called a WordPress function before WordPress loaded, or a theme/plugin file was opened directly.

Cannot redeclarePHP

Fatal error: Cannot redeclare function foo() (previously declared in …)

The same function (or class) was defined twice — usually a file included more than once.

ZeroDivisionErrorPython

ZeroDivisionError: division by zero

A number was divided (or modulo’d) by zero.

Allowed memory size exhaustedPHP

PHP Fatal error: Allowed memory size of X bytes exhausted

The script tried to use more memory than PHP’s `memory_limit` allows.

Plugin could not be activated because it triggered a fatal errorWordPress

WordPress: Plugin could not be activated because it triggered a fatal error

Activating the plugin caused a PHP fatal error — usually PHP version incompatibility, a conflict with another plugin/theme, or mi…

Division by zeroSQL

SQL Error: division by zero / Divide by zero error encountered

An expression divided by a value that was 0 for at least one row.

Cannot use object as arrayPHP

Fatal error: Uncaught Error: Cannot use object of type stdClass as array

Code used array syntax (`$x['key']`) on an object.

Two steps away (28)

500HTTP

HTTP 500 Internal Server Error

The server hit an unexpected condition — usually an unhandled exception or misconfiguration in the application.

Class not foundPHP

PHP Fatal error: Uncaught Error: Class "X" not found

PHP couldn’t load the class — autoloading failed, the namespace is wrong, or the dependency isn’t installed.

Headers already sentPHP

Warning: Cannot modify header information - headers already sent

You called `header()`, `setcookie()` or `session_start()` after output had already been sent to the browser.

NullReferenceException.NET

System.NullReferenceException: Object reference not set to an instance of an object

Code dereferenced a variable that is `null` — the .NET equivalent of Java’s NullPointerException.

Maximum execution timePHP

PHP Fatal error: Maximum execution time of 30 seconds exceeded

The script ran longer than `max_execution_time` and PHP stopped it.

Parse errorPHP

PHP Parse error: syntax error, unexpected …

PHP can’t parse the file because of a syntax mistake — the real error is often on the line before the one reported.

Critical errorWordPress

WordPress: There Has Been a Critical Error on This Website

A PHP fatal error (usually from a plugin or theme) stopped WordPress; the real error is in the debug log or recovery-mode email.

TypeErrorPHP

Fatal error: Uncaught TypeError: foo(): Argument #1 ($x) must be of type int, string given

A function received a value of the wrong type for a typed parameter.

mysqli_sql_exceptionPHP

Fatal error: Uncaught mysqli_sql_exception

A MySQLi query or connection failed; since PHP 8.1 MySQLi throws exceptions by default.

Maximum function nestingPHP

Fatal error: Maximum function nesting level of '256' reached, aborting!

Recursion went deeper than Xdebug’s max_nesting_level allows (or PHP crashed with a segfault without Xdebug).

Installation failed: Could not create directoryWordPress

WordPress: Installation failed: Could not create directory (plugin/theme install or update)

WordPress can’t write to wp-content/plugins, themes or upgrade — ownership/permissions or disk space.

Please enter your FTP credentialsWordPress

To perform the requested action, WordPress needs to access your web server. Please enter your FTP credentials to proceed

WordPress can’t write directly to its files (ownership differs from the PHP user), so it falls back to asking for FTP details.

failed to open streamPHP

Warning: include(x.php): Failed to open stream: No such file or directory

PHP couldn’t open a file for include/require/fopen — wrong path, missing file, or no permission.

Uncaught ExceptionPHP

Fatal error: Uncaught Exception: message in file.php:12

An exception was thrown and nothing caught it, so PHP stopped the script.

ReferenceErrorJavaScript

ReferenceError: x is not defined

Code refers to a variable or function name that doesn’t exist in the current scope.

RangeErrorJavaScript

RangeError: Maximum call stack size exceeded

A function called itself (directly or indirectly) too many times — usually infinite recursion.

KeyErrorPython

KeyError: 'x'

You accessed a dictionary key that doesn’t exist.

OOMKilledKubernetes

Kubernetes: OOMKilled (exit code 137)

The container used more memory than its limit, and the kernel killed it.

413HTTP

HTTP 413 Content Too Large (Request Entity Too Large)

The request body is bigger than the server is willing to accept — usually a file upload over the configured limit.

OutOfMemoryErrorJava

java.lang.OutOfMemoryError: Java heap space

The JVM ran out of heap memory and garbage collection couldn’t free enough.

Destination folder already existsWordPress

WordPress: Destination folder already exists. Plugin installation failed

A folder with the plugin/theme’s name already exists in wp-content, usually from a failed or partial previous install.

No valid plugins were foundWordPress

The package could not be installed. No valid plugins were found

The uploaded zip doesn’t contain a plugin main file with a plugin header at the expected level — often a zip of zips, a theme, or…

requires at least PHPWordPress

WordPress: Your server is running PHP version 7.2 but WordPress 6.x requires at least 7.4 / This plugin requires a newer version of PHP

WordPress core, a plugin or a theme needs a newer PHP than the server runs.

TypeError: NoneTypePython

TypeError: 'NoneType' object is not subscriptable

You used `[ ]` on a value that is `None` — typically a function that returned nothing.

GROUP BYSQL

Column must appear in the GROUP BY clause / isn't in GROUP BY (MySQL 1055 only_full_group_by)

You selected a column that is neither grouped nor aggregated, so the result would be ambiguous.

ClassCastExceptionJava

java.lang.ClassCastException: class A cannot be cast to class B

An object was cast to a type it isn’t.

Array to string conversionPHP

Warning: Array to string conversion

An array was used where a string is expected — echoing it, concatenating it, or passing it to a string function.

Unsupported operand typesPHP

Fatal error: Uncaught TypeError: Unsupported operand types: string + int

An arithmetic or array operator was used with incompatible types (PHP 8 is stricter than PHP 7).