Common Causes of the "Document Not Found" Error in Next.js
- Incorrect Routing Setup: Next.js relies on a file-based routing system. A "Document Not Found" error can occur if there is a typo in the file or folder names within the
pages
directory. For example, if you navigate to /about
but the file is misnamed as abot.js
, this error will appear.
- Static Generation or Server-Side Rendering Issues: When using static generation or server-side rendering, a missing or incorrectly coded
getStaticProps
or getServerSideProps
method can result in a "Document Not Found" error. If these functions fail to fetch required data or return notFound: true
, the page will not be rendered.
- Misconfigured Dynamic Routes: Using dynamic routing in Next.js with square brackets (e.g.,
[id].js
) can lead to these errors if the parameters are incorrect or not handled properly within the page. For instance, if you have a route like /post/[id]
but the id parameter passed is invalid or missing, the error may arise.
- Missing API Route Files: If you are trying to interact with API routes, the absence of a defined handler in the corresponding
pages/api
directory for the requested API endpoint can prompt this error. Ensuring the API route file aligns perfectly with the requested endpoint is crucial.
- Page Not Exporting Correctly: Failing to export a JavaScript module from a page file makes it unavailable for rendering, thus leading to a "Document Not Found" error. Always confirm that each page exports a default function or component.
- Mistyped Links or Paths: Links or paths within the app must be correctly spelled and formatted. Incorrect use of the
Link
component or href
attributes with errors or typos can easily lead to navigating to a non-existent resource.
- Build Errors: Next.js build errors, especially in production, can prevent certain pages from being generated correctly, leading to "Document Not Found" alerts. Such issues often stem from incorrect module imports or unresolved dependencies in the build process.
// Example of a potential typo in a getStaticProps function causing an error
export async function getStaticProps() {
const res = await fetch('https://api.example.com/data');
if (!res.ok) {
return {
notFound: true,
}
}
const data = await res.json();
return {
props: { data }, // Make sure to return the data correctly
}
}