Error map
Prerender error Error occurred prerendering page "/x". Read more: https://nextjs.org/docs/messages/prerender-error
React · layer 1, On your device
Centre: this error. First ring: errors it is linked with (12). 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.
Directly related (12)
dial tcp: lookup registry-1.docker.io: no such host / Temporary failure in name resolution during docker build
DNS isn’t working for the Docker daemon or inside build containers, so pulls and package downloads fail.
Module parse failed: Unexpected token. You may need an appropriate loader to handle this file type
Webpack found syntax it can’t parse because no loader is configured for that file (JSX, TypeScript, CSS, or modern syntax in node…
Error: Functions cannot be passed directly to Client Components unless you explicitly expose it by marking it with "use server".
A Server Component passed a function prop to a Client Component.
Error: Hydration failed because the initial UI does not match what was rendered on the server
The HTML rendered on the server differs from the first client render, so React (Next.js/Remix) can’t attach to it.
Error: Invalid src prop on `next/image`, hostname "x" is not configured under images in your `next.config.js`
next/image refuses to optimize images from domains not allowed in next.config.js.
Error: async/await is not yet supported in Client Components, only Server Components.
A component marked "use client" was declared async.
Dockerfile parse error line N: unknown instruction
A line in the Dockerfile doesn’t start with a valid instruction — usually a broken line continuation or a typo.
Cloudflare Pages build: Error: Output directory "dist" not found / Failed: build output directory not found
The Pages build finished, but the folder set as “Build output directory” doesn’t exist — the framework wrote its files somewhere…
error NETSDK1045: The current .NET SDK does not support targeting .NET 8.0. Either target .NET 7.0 or lower, or use a version of the .NET SDK that supports .NET 8.0
The installed .NET SDK is older than the project’s TargetFramework.
Module not found: Can't resolve 'fs' (Next.js / webpack 5)
A Node.js built-in (fs, path, crypto, net) is imported into code that runs in the browser bundle.
You're importing a component that needs useState. It only works in a Client Component but none of its parents are marked with "use client"
In the Next.js App Router, a component using hooks or browser APIs is rendered as a Server Component.
Error: Dynamic server usage: Route /x couldn't be rendered statically because it used `cookies`
Next.js tried to statically render a route that reads request-specific data (cookies, headers, searchParams).
Two steps away (27)
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.
HTTP 408 Request Timeout
The server closed the connection because the client took too long to send the complete request.
TypeError: Failed to fetch / NetworkError when attempting to fetch resource
The browser couldn’t complete the request at the network level — CORS, DNS, offline, blocked mixed content, or the server refused…
COPY failed: file not found in build context / "/app/x": not found
The Dockerfile COPY refers to a path outside the build context, excluded by .dockerignore, or relative to the wrong directory.
Error: Could not find or load main class org.gradle.wrapper.GradleWrapperMain
The Gradle wrapper JAR (gradle/wrapper/gradle-wrapper.jar) is missing or corrupt.
ChunkLoadError: Loading chunk 123 failed.
A lazily loaded JavaScript chunk couldn’t be downloaded — usually because a new deployment removed the old hashed files.
Error: NextRouter was not mounted.
next/router’s useRouter was used inside the App Router (app/ directory), which uses next/navigation instead.
Next.js: You're importing a component that needs "server-only". That only works in a Server Component
A Client Component (or a file it imports) pulls in server-only code — database clients, secrets, next/headers or a module marked…
ReferenceError: x is not defined
Code refers to a variable or function name that doesn’t exist in the current scope.
Error: Objects are not valid as a React child
You tried to render a plain object (or a Promise/Date) directly in JSX; React can only render strings, numbers, elements and arra…
Error: Invalid hook call. Hooks can only be called inside of the body of a function component.
A hook ran outside a function component/custom hook, conditionally — or two copies of React are loaded.
Kubernetes: ImagePullBackOff / ErrImagePull
The node can’t pull the container image — wrong name/tag, missing registry credentials, or registry unreachable.
exec /usr/local/bin/docker-entrypoint.sh: exec format error
The container tried to run a binary built for a different CPU architecture (arm64 vs amd64) — or a script with a broken shebang /…
conflict: unable to remove repository reference (must force) - container is using its referenced image
You tried to delete an image that a container — even a stopped one — still uses.
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.
IndentationError: unexpected indent / expected an indented block
Python’s block structure is broken — inconsistent indentation or mixed tabs and spaces.
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…
gyp ERR! build error / node-gyp rebuild failed
A dependency with native C/C++ code couldn’t compile — missing build tools, Python, or an unsupported Node version.
Error: error:0308010C:digital envelope routines::unsupported
An old build tool (webpack 4, old react-scripts) uses a hash algorithm that OpenSSL 3 in Node 17+ disables.
Error: @prisma/client did not initialize yet. Please run "prisma generate"
The generated Prisma Client is missing or out of date.
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).
Error: Node Sass does not yet support your current environment
node-sass (deprecated) has no binary for your Node version/OS.
Laravel: Vite manifest not found at: public/build/manifest.json
Laravel’s @vite directive can’t find the compiled asset manifest because assets weren’t built.
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.
Warning: Each child in a list should have a unique "key" prop
When rendering a list with `.map()`, each element needs a stable, unique `key` so React can track items between renders.
Error: Element type is invalid: expected a string (for built-in components) or a class/function (for composite components) but got: undefined
JSX referenced a component that is undefined — almost always a default/named import mismatch.
Warning: Cannot update a component (`Parent`) while rendering a different component (`Child`)
A child component updated a parent’s state during its render instead of in an effect or event handler.
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