Error map

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

PHP · layer 4, Application & API

Open the full error page →

Centre: this error. First ring: errors it is linked with (7). Outer ring: what those are linked with. Colours show the layer of a request each error belongs to. Click any dot to re-centre the map on it; hover to follow its connections. The centre dot opens the error page.

1 · On your device 2 · Network 4 · Application & API 5 · Data 6 · Platform & cloud 7 · Build & delivery
Class not found — PHP Fatal error: Uncaught Error: Class "X" not found (PHP)Class not f…ClassNotFoundException — java.lang.ClassNotFoundException / NoClassDefFoundError (Java)ClassNotFoundExcept…Call to undefined function — PHP Fatal error: Uncaught Error: Call to undefined function (PHP)Call to undefined f…ModuleNotFoundError — ModuleNotFoundError: No module named 'x' (Python)ModuleNotFoundErrorComposer conflict — Your requirements could not be resolved to an installable set of packages. (PHP)Composer conflictintl missing — Class "NumberFormatter" not found / The "intl" PHP extension is required (PHP)intl missingComposer memory — Composer: PHP Fatal error: Allowed memory size of 1610612736 bytes exhausted (PHP)Composer memoryTarget class does not exist — Laravel: Target class [App\Http\Controllers\X] does not exist. (PHP)Target class does n…Could not resolve — Gradle: Could not resolve all files for configuration / Could not resolve dependency (Android)Could not resolveNullPointerException — java.lang.NullPointerException (Java)NullPointerExceptionFileNotFoundException assembly — Could not load file or assembly 'X, Version=…' or one of its dependencies (.NET)FileNotFoundExcepti…500 — HTTP 500 Internal Server Error (HTTP)500Headers already sent — Warning: Cannot modify header information - headers already sent (PHP)Headers already sentCritical error — WordPress: There Has Been a Critical Error on This Website (WordPress)Critical errorMODULE_NOT_FOUND — Error: Cannot find module 'x' (MODULE_NOT_FOUND) (Node.js)MODULE_NOT_FOUNDImportError — ImportError: cannot import name 'x' from 'y' (Python)ImportErrorNameError — NameError: name 'x' is not defined (Python)NameErrorERESOLVE — npm ERR! code ERESOLVE — unable to resolve dependency tree (npm)ERESOLVEDuplicate class — Duplicate class X found in modules A and B (Android)Duplicate classCocoaPods compatible versions — CocoaPods could not find compatible versions for pod (iOS)CocoaPods compatibl…could not find driver — PDOException: could not find driver (PHP)could not find driv…GD missing — Fatal error: Uncaught Error: Call to undefined function imagecreatefromjpeg() (PHP)GD missing42883 function — ERROR: function x(text) does not exist — No function matches the given name and argument types (PostgreSQL)42883 functionAllowed memory size exhausted — PHP Fatal error: Allowed memory size of X bytes exhausted (PHP)Allowed memory size…OOM killer — Killed / Out of memory: Killed process (Linux OOM killer) (Linux)OOM killerCall to member function on null — Fatal error: Uncaught Error: Call to a member function x() on null (PHP)Call to member func…No application encryption key — Laravel: No application encryption key has been specified. (PHP)No application encr…419 Page Expired — Laravel: 419 Page Expired (CSRF token mismatch) (PHP)419 Page ExpiredLaravel table not found — Laravel: SQLSTATE[42S02]: Base table or view not found: 1146 Table 'db.sessions' doesn't exist (PHP)Laravel table not f…

Directly related (7)

ClassNotFoundExceptionJava

java.lang.ClassNotFoundException / NoClassDefFoundError

The JVM couldn’t find a class on the classpath at runtime.

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.

ModuleNotFoundErrorPython

ModuleNotFoundError: No module named 'x'

Python can’t find the module you import — it isn’t installed in the interpreter/virtualenv that’s running, or the import path is…

Composer conflictPHP

Your requirements could not be resolved to an installable set of packages.

Composer can’t find package versions that satisfy every constraint (PHP version, extensions, other packages).

intl missingPHP

Class "NumberFormatter" not found / The "intl" PHP extension is required

Code uses the intl extension (NumberFormatter, Collator, IntlDateFormatter) but it isn’t installed.

Composer memoryPHP

Composer: PHP Fatal error: Allowed memory size of 1610612736 bytes exhausted

Composer ran out of memory while resolving or installing dependencies.

Target class does not existPHP

Laravel: Target class [App\Http\Controllers\X] does not exist.

Laravel’s container couldn’t find the controller or class named in a route or binding.

Two steps away (21)

Could not resolveAndroid

Gradle: Could not resolve all files for configuration / Could not resolve dependency

Gradle couldn’t download a dependency — wrong coordinates/version, missing repository, offline mode, or network/proxy issues.

NullPointerExceptionJava

java.lang.NullPointerException

Code called a method or accessed a field on a reference that is `null`.

FileNotFoundException assembly.NET

Could not load file or assembly 'X, Version=…' or one of its dependencies

The runtime couldn’t find or load a referenced DLL — missing from the output, wrong version, or wrong platform (x86/x64).

500HTTP

HTTP 500 Internal Server Error

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

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.

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.

MODULE_NOT_FOUNDNode.js

Error: Cannot find module 'x' (MODULE_NOT_FOUND)

Node can’t resolve the module path — the package isn’t installed, or a relative path/extension is wrong.

ImportErrorPython

ImportError: cannot import name 'x' from 'y'

The module was found, but the name you’re importing from it doesn’t exist — usually a version change or a circular import.

NameErrorPython

NameError: name 'x' is not defined

Python doesn’t know the name — it was never assigned/imported in this scope, or it’s misspelled.

ERESOLVEnpm

npm ERR! code ERESOLVE — unable to resolve dependency tree

npm 7+ found conflicting peer dependency requirements and refuses to install a broken tree.

Duplicate classAndroid

Duplicate class X found in modules A and B

Two dependencies ship the same class — typically old Android Support libraries mixed with AndroidX, or Kotlin stdlib-jdk7/jdk8 ve…

CocoaPods compatible versionsiOS

CocoaPods could not find compatible versions for pod

pod install can’t satisfy the version constraints — outdated spec repo, a higher deployment target required, or two pods needing…

could not find driverPHP

PDOException: could not find driver

The PDO driver for your database (pdo_mysql, pdo_pgsql, pdo_sqlite) isn’t installed or enabled.

GD missingPHP

Fatal error: Uncaught Error: Call to undefined function imagecreatefromjpeg()

The GD extension (or its JPEG/WebP support) isn’t installed for the PHP version serving the site.

42883 functionPostgreSQL

ERROR: function x(text) does not exist — No function matches the given name and argument types

PostgreSQL found no function with that name and argument types — wrong types, missing extension, or schema not in search_path.

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.

OOM killerLinux

Killed / Out of memory: Killed process (Linux OOM killer)

The kernel ran out of memory and killed a process to recover — the program just prints “Killed” (exit code 137).

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.

No application encryption keyPHP

Laravel: No application encryption key has been specified.

Laravel’s APP_KEY is missing, so it can’t encrypt sessions and cookies.

419 Page ExpiredPHP

Laravel: 419 Page Expired (CSRF token mismatch)

Laravel rejected a POST because the CSRF token was missing, expired or didn’t match the session.

Laravel table not foundPHP

Laravel: SQLSTATE[42S02]: Base table or view not found: 1146 Table 'db.sessions' doesn't exist

Laravel queried a table that hasn’t been created — usually sessions, cache, jobs or a new model’s table.

Map another error

Popular: 4035004000xC000007BTypeErrorCritical error404NullPointerException