When running next build on the latest canary version (13.4.20-canary.9, the following error occurs.

> Build error occurred
[Error: ENOENT: no such file or directory, rename '/vercel/path0/.next/export/404.html' -> '/vercel/path0/.next/server/pages/404.html'] {
  errno: -2,
  code: 'ENOENT',
  syscall: 'rename',
  path: '/vercel/path0/.next/export/404.html',
  dest: '/vercel/path0/.next/server/pages/404.html'
}

I have my error pages in a (folder) to keep them away from other things.