As described within Multi-Page Apps and URL Support | Dash for Python Documentation | Plotly , creating a /pages/not_found_404.py file allows you to define custom 404 functionality. However when I try to do the same using: dash.register_page("not_found_404", layout=html.Div("not_found_404")) it d…

Hi @marketemp This is the same issue as your other post - see more info here: Bug - Dash Pages does not find pages with underscores - #2 by AnnMarieW

Hi @AnnMarieW I understand it’s the same issue with underscores, but I cannot determine how to resolve it correctly using that feedback or any of the examples?

Did you run the example I posted in the other topic? It’s common to use underscores in the module name. Path with underscores (not recommended) register_page("my_page", layout=html.Div("my_page"), path="/my_page") [image] Path with dashes (the defualt) register_page("my_home_page", layout=html.…

I understand that already for pages I’ve defined. What I’m asking is how to get dash.register_page("not_found_404", layout=html.Div("not_found_404")) to work. I can only get this working using /pages/not_found_404.py

nope that does not work with any of the variants register_page(__name__) layout = ... or register_page('not_found_404", layout='...') or register_page('not-found-404", layout='...') → The page is registered as /not-found-404, but it does NOT serve as custom 404 page as described here: Multi-Pag…

@marketemp try updating to the latest Dash. I think this was actually caused by a known bug where custom 404 pages (whether set by a pages/not_found_404.py or by an inline dash.register_page("not_found_404", layout)) didn’t work with Dash Pages. This was fixed in Dash 2.7.0.

Bug - cannot register not_found_404 with dash.register_page()

Dash Python

jinnyzor October 30, 2022, 12:58am 6

The docs say to name it

_ _ name _ _ ← can’t use code tags on phone…

Instead of trying to use the underscores.

Maybe that is the issue somehow?

Multipaging with custom 404 page and pages_folder does not work as expected

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Bug - cannot register not_found_404 with dash.register_page()

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