Error map

Unhandled 'error' event Error: Unhandled 'error' event (events.js / node:events)

Node.js · layer 4, Application & API

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1 · On your device 2 · Network 4 · Application & API 6 · Platform & cloud 7 · Build & delivery
Unhandled 'error' event — Error: Unhandled 'error' event (events.js / node:events) (Node.js)Unhandled '…MODULE_NOT_FOUND — Error: Cannot find module 'x' (MODULE_NOT_FOUND) (Node.js)MODULE_NOT_FOUNDMaxListenersExceededWarning — MaxListenersExceededWarning: Possible EventEmitter memory leak detected. 11 listeners added (Node.js)MaxListenersExceede…SyntaxError import — SyntaxError: Cannot use import statement outside a module (Node.js)SyntaxError importlisten EACCES — Error: listen EACCES: permission denied 0.0.0.0:80 (Node.js)listen EACCESEADDRINUSE — Error: listen EADDRINUSE: address already in use :::3000 (Node.js)EADDRINUSEDEP0005 — DeprecationWarning: Buffer() is deprecated due to security and usability issues (DEP0005) (Node.js)DEP0005DEP0040 — DeprecationWarning: The `punycode` module is deprecated (DEP0040) (Node.js)DEP0040ERESOLVE — npm ERR! code ERESOLVE — unable to resolve dependency tree (npm)ERESOLVEENOENT — Error: ENOENT: no such file or directory (Node.js)ENOENTTypeError: not a function — TypeError: x is not a function (JavaScript)TypeError: not a fu…OOMKilled — Kubernetes: OOMKilled (exit code 137) (Kubernetes)OOMKilledOutOfMemoryError — java.lang.OutOfMemoryError: Java heap space (Java)OutOfMemoryErrorMEMORY_MANAGEMENT — Blue Screen: MEMORY_MANAGEMENT (Stop code 0x0000001A) (Windows)MEMORY_MANAGEMENTReferenceError — ReferenceError: x is not defined (JavaScript)ReferenceErrorERR_REQUIRE_ESM — Error [ERR_REQUIRE_ESM]: require() of ES Module not supported (Node.js)ERR_REQUIRE_ESMERR_HTTP_HEADERS_SENT — Error [ERR_HTTP_HEADERS_SENT]: Cannot set headers after they are sent to the client (Node.js)ERR_HTTP_HEADERS_SE…daemon — Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running? (Docker)daemonport is already allocated — Docker: Bind for 0.0.0.0:80 failed: port is already allocated (Docker)port is already all…403 — HTTP 403 Forbidden (HTTP)403ECONNREFUSED — Error: connect ECONNREFUSED 127.0.0.1:5432 (Node.js)ECONNREFUSEDELIFECYCLE — npm ERR! code ELIFECYCLE / Command failed with exit code 1 (npm)ELIFECYCLEPort 8080 in use — Web server failed to start. Port 8080 was already in use. (Java)Port 8080 in useERR_IMPORT_ATTRIBUTE_MISSING — TypeError [ERR_IMPORT_ATTRIBUTE_MISSING]: Module needs an import attribute of "type: json" (Node.js)ERR_IMPORT_ATTRIBUT…EBADENGINE — npm WARN EBADENGINE Unsupported engine / The engine "node" is incompatible with this module (Node.js)EBADENGINEreq.body undefined — Express: req.body is undefined / {} (body parser missing) (Node.js)req.body undefinedCould not resolve — Gradle: Could not resolve all files for configuration / Could not resolve dependency (Android)Could not resolveClassNotFoundException — java.lang.ClassNotFoundException / NoClassDefFoundError (Java)ClassNotFoundExcept…CocoaPods compatible versions — CocoaPods could not find compatible versions for pod (iOS)CocoaPods compatibl…

Directly related (7)

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.

MaxListenersExceededWarningNode.js

MaxListenersExceededWarning: Possible EventEmitter memory leak detected. 11 listeners added

More than 10 listeners were added to one event — often a leak where listeners are added repeatedly.

SyntaxError importNode.js

SyntaxError: Cannot use import statement outside a module

An `import` statement ran in a context treated as CommonJS (Node without "type": "module", a browser script without type="module"…

listen EACCESNode.js

Error: listen EACCES: permission denied 0.0.0.0:80

Node isn’t allowed to bind that port — ports below 1024 need root on Linux/macOS, and some Windows ports are reserved.

EADDRINUSENode.js

Error: listen EADDRINUSE: address already in use :::3000

Another process is already listening on that port.

DEP0005Node.js

DeprecationWarning: Buffer() is deprecated due to security and usability issues (DEP0005)

Code (yours or a dependency) uses the deprecated new Buffer() constructor.

DEP0040Node.js

DeprecationWarning: The `punycode` module is deprecated (DEP0040)

A dependency imports Node’s built-in punycode module, deprecated since Node 21.

Two steps away (21)

ERESOLVEnpm

npm ERR! code ERESOLVE — unable to resolve dependency tree

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

ENOENTNode.js

Error: ENOENT: no such file or directory

A file or directory the program tried to open doesn’t exist at that path.

TypeError: not a functionJavaScript

TypeError: x is not a function

You called something as a function, but its value is not a function (it’s undefined, a string, an object…).

OOMKilledKubernetes

Kubernetes: OOMKilled (exit code 137)

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

OutOfMemoryErrorJava

java.lang.OutOfMemoryError: Java heap space

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

MEMORY_MANAGEMENTWindows

Blue Screen: MEMORY_MANAGEMENT (Stop code 0x0000001A)

Windows detected a severe memory-management error — commonly faulty RAM, unstable memory settings or a bad driver.

ReferenceErrorJavaScript

ReferenceError: x is not defined

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

ERR_REQUIRE_ESMNode.js

Error [ERR_REQUIRE_ESM]: require() of ES Module not supported

CommonJS code used `require()` on a package that is ES-module-only (node-fetch 3, chalk 5, nanoid 4, got 12…).

ERR_HTTP_HEADERS_SENTNode.js

Error [ERR_HTTP_HEADERS_SENT]: Cannot set headers after they are sent to the client

An Express/Node handler tried to send a second response (or set headers) after one was already sent.

daemonDocker

Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?

The docker CLI can’t talk to the Docker engine — it isn’t running, or your user can’t access the socket.

port is already allocatedDocker

Docker: Bind for 0.0.0.0:80 failed: port is already allocated

Another container or host process already publishes that host port.

403HTTP

HTTP 403 Forbidden

The server understood the request but refuses to authorize it — you (or the server process) are not allowed to access this resour…

ECONNREFUSEDNode.js

Error: connect ECONNREFUSED 127.0.0.1:5432

Nothing is listening at that host:port — the target service is down or you’re connecting to the wrong address.

ELIFECYCLEnpm

npm ERR! code ELIFECYCLE / Command failed with exit code 1

An npm script (build, start, test, postinstall) exited with an error. ELIFECYCLE is only the wrapper — the real error is printed…

Port 8080 in useJava

Web server failed to start. Port 8080 was already in use.

Spring Boot couldn’t bind its embedded server port because another process uses it.

ERR_IMPORT_ATTRIBUTE_MISSINGNode.js

TypeError [ERR_IMPORT_ATTRIBUTE_MISSING]: Module needs an import attribute of "type: json"

An ES module imported a .json file without the required import attribute.

EBADENGINENode.js

npm WARN EBADENGINE Unsupported engine / The engine "node" is incompatible with this module

A package requires a different Node.js version than the one you’re running.

req.body undefinedNode.js

Express: req.body is undefined / {} (body parser missing)

Express didn’t parse the request body because no body-parsing middleware matched the request’s Content-Type.

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.

ClassNotFoundExceptionJava

java.lang.ClassNotFoundException / NoClassDefFoundError

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

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…

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