What should I do if I encounter a '404 Page not found' error while applying for a 60-day visa through the Frankfurt e-visa system?

Clear browser cache.

It's also partial to certain browsers, just throwing that out there

Mine took 14 days to come thru. I tried everything. The best solution was to practice completing the form to make sure I filled it correctly. Photo with white background and size etc. also check that when the passport is read misreading has not crept in. If all was good do not submit and wait. If thy do indeed need further documentation wait for e mail. If not wait a little longer mine came on the last day. I tried an e mail to uk visa office that might have helped in the end believe it’s down to them. Good luck

clean your cache and cookies and try again it should work.

On the USA site I had trouble until I sent jpegs (pictures of the documents)

J Peg

Its the same system regardless of country. Unstable internet connection? using VPN?

Or just try again tomorrow