Homeassistant and node-red ui fail

Third party integrations Node-RED
1

I have a running homeassistant installation running fine. Most parts of my automation are done in node-red. I also have some node-red ui screens.

All is running on a Pi 4. with SD card. I wanted to upgrade hardware to Pi 5 with SSD.
I installed Homeassistant on the new hardware using the Pi Immager. After startup I planned do load a backup that I made from the runnig system. This did not work as the backup was made with 2025.11.5 and the sofware fresh installed was 2025.11.1. I did not finda way to upgrade from the inital screen where I get the option to start a HA or load a backup.
So I had to start HA and let it initialize before I could update to 2025.11.5.
Now loading the full backup worked ok. The system initialised and everyting looked ok…
One exeption that I now spend 3 days and night trying to solve, including help from chatGPT. When I call :1880/ut i get a standard box request for username/password. After that a simple:
Cannot GET /ui.
What ever I tried, no solution yet,

Now I tryed fresh install Homeassistant. Initialise a home. Install add-on node-red.
Create a simple node-red flow with a ui.
Same result:

> Cannot GET /ui
I’m stuck here.

Note: node-red is running the flows, I verified. I can get to the node-red flows either from the HA screen or direct with :1880.Only I cannot get to the node-red UI.
This does not seem te be a node-red problem.
HELP!

2

Maybe a missing setting in th addon configuration page.
Check especially the ones that are under the disabled option section lines.

3

If you are running Node-RED as an add-on, Home Assistant runs all access to add-ons via the ‘endpoint’ which provides unified authorization through HA.

The address for direct access to Node-RED dashboard (the /ui) is

http://homeassistant.local:1880/endpoint/ui

or whatever your HA IP address is.

You will have to provide the HA user id and password to gain access to the HA endpoint, as you have already noted.

Add:

If you start Node-RED (add-on) and look at the logs, you will find

Welcome to Node-RED
===================
2 Dec 21:39:01 - [info] Node-RED version: v4.0.9
2 Dec 21:39:01 - [info] Node.js  version: v22.16.0
2 Dec 21:39:01 - [info] Linux 6.12.51-haos arm64 LE
2 Dec 21:39:02 - [info] Loading palette nodes
2 Dec 21:39:03 - [info] Node-RED Contrib Theme Collection version: v4.0.11
2 Dec 21:39:09 - [info] Dashboard version 3.6.5 started at /endpoint/ui

where Dashboard (version) started at /endpoint/ui

tells you where you can find it.

4

As noted, the Node-RED add-on requires you to access your dashboard via /endpoint/ui. If this is not to your liking, the Node-RED Plus add-on offers the ability to access your dashboard with just /ui.

Note that the Node-RED Plus add-on comes with FlowFuse Dashboard (2.0) pre-installed, but you can still install the deprecated node-red-dashboard through the add-on configuration or with the Node-RED palette manager.