Most issues come down to how a build references its assets. Here are the common ones.
”Check base path” warning, or a blank page
Cause: the build was made with an absolute base — it assumes it’s served from the domain root,
so asset links look like /assets/app.js instead of assets/app.js.
Fix: rebuild with a relative base and re-upload:
// Vite
export default { base: './' };// Create React App (package.json)
{ "homepage": "." }App To Page rewrites root-absolute paths on upload as a safety net, so an absolute build mounted at its exact slug usually still works — but a relative build is portable and warning-free. See Deploy a Vite or React app.
A deep link or refresh shows a 404
Cause: a client-side router (React Router, Vue Router) owns sub-paths, but SPA fallback is off.
Fix: make sure SPA fallback is enabled for the app (it’s on by default). With it on, unknown
sub-paths serve your index.html so the router can handle the route.
Some assets load, others 404
Cause: assets referenced with absolute paths, or files that live outside the build output.
Fix: reference assets relatively, and make sure every asset (models, fonts, images) is inside
the folder you zipped. For frameworks, put static files in public/ so they land in dist/.
”Files missing” on an app card
Cause: the app’s files couldn’t be found on disk — usually from an interrupted upload.
Fix: use ⋯ → Update on the card and re-upload the zip. See Update an app in place.
My zip has an extra wrapping folder
App To Page automatically strips a single wrapping folder (like dist/, or the wrapper macOS adds
when you compress a folder), then locates index.html. If your archive nests index.html several
folders deep, re-zip the contents of your build folder so index.html is at the top.
Still stuck?
Make sure your archive has a top-level index.html, uses relative asset paths, and was built for
production. If it runs when you open index.html locally and still won’t serve, get in touch and
we’ll help you sort it out.