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docz/docs/09-miscellany/02-errors.md

@@ -100,6 +100,35 @@ server with NodeJS or some other server-side technology.
 
 If the files are small, please [report to our issue tracker](https://git.sheetjs.com/sheetjs/sheetjs/issues)
 
+#### Invalid HTML: could not find table
+
+Data can be fetched and parsed by the library:
+
+```js
+const response = await fetch("test.xlsx");
+const wb = XLSX.read(await response.arrayBuffer());
+```
+
+If the file does not exist, servers will send a 404 response that may include a
+friendly HTML page. Without checking the response code, the integration will try
+to read the 404 page and fail since the HTML typically has no TABLE elements.
+
+When building a project with CRA or other templates, spreadsheets must be placed
+in the `public` folder. That folder is served by the dev server and copied in
+the build process.
+
+Integration code should defend against network issues by checking status code.
+For example, when using `fetch`:
+
+```js
+async function fetch_workbook_and_error_on_404(url) {
+  const response = await fetch(url);
+  if(res.status == 404) throw new Error("404 File Not Found");
+  const ab = await response.arrayBuffer();
+  return XLSX.read(ab);
+}
+```
+
 #### SCRIPT5022: DataCloneError
 
 IE10 does not properly support `Transferable`.