Home Assistant Certificate Authority is not trusted, only in tablet

[hawk100 (A H)]

I have been having this issue for a while, on my Android tablet (old Nexus 7), but also on a more modern Pixel 6a phone. (also on Lenovo m8 tablet)

I can click/press away from the message and use HA and have been doing that but it is not a solution.

Finally decided to try and find a solution for my scenario.

Looked at the following posts that appear to be directly or indirectly relevant - as far as I understand them:

SSL not working

@Ajaxhan_Anna My working config looks like this: # Configure a default setup of Home Assistant (frontend, api, etc) default_config: # Uncomment this if you are using SSL/TLS, running in Docker container, etc. http: base_url: https://changetoyours.duckdns.org server_port: 8123 ssl_certificate: /ssl/fullchain.pem ssl_key: /ssl/privkey.pem # Text to speech tts: platform: google_translate group: !include groups.yaml automation: !include automations.yaml script: !include scripts.y…

Local pages not secure

My Supervised HA has been loading pages securely from day 1 over 18 months ago just using the default 8123 port and inbuilt config. I.e. I knew nothing about security certificates and had not done anything beyond initial default config. I would enter the local IP address in any browser and the pages would load securely. A few days ago I wanted to make a small change to an ESPHome device yaml file but the file would not install as it could not find the device wifi IP address despite HA control…

Latest version of Companion App unable to connect to local HA server using SSL

I noticed one of my mounted tablets was having connection issues today. It reported an ssl issue and that I needed to check my connections. I’m using Letsencrypt and cert is valid. I confirmed this tablet was on the latest version of the companion app. I was able to access from my PC without issues. I checked my other tablet and it was working fine. I proceeded to update it to the latest version of the app and it too now reports: “The Home Assistant Certificate authority is not trusted…” …

https://www.reddit.com/r/homeassistant/comments/1c44s04/ssl_certificate_trust_issue_with_home_assistant/
https://www.reddit.com/r/homeassistant/comments/1cnwtjj/companion_app_android_issue_ha_certificate/
https://www.reddit.com/r/homeassistant/comments/19ac4r8/the_home_assistant_certificate_authority_is_not/
https://www.reddit.com/r/homeassistant/comments/1erg7yg/home_assistant_certificate_authority_is_not/

Companion App does not connect with bad SSL certificates

I set up my Home Assistant to be available outside of local network using Cloudflare, Cloudflare add-on and Let’s Encrypt addon. Certificates are created for my external address (domain) specifically. Every time I try to connect to a local address of Home Assistant using a web browser, I need to click “Trust” in order to connect to the address because the certificate does not correspond to the URL. Home Assistant Companion just refuses to connect at all, and there is no option to “Trust” the ce…

Let Home Assistant trust a personal certificate authority

Hello everyone! I’m using a personal certificate authority which I add to the trusted CAs of any of my devices so that they can identify other devices that I usually don’t permit to have internet access, which is partially why I’m not using a service like Let’s Encrypt for that matter. I also have such a “locally” signed certificate in my HomeMatic CCU and I would like to enable the verify_ssl option in the homematic integration. Sadly, I didn’t manage to locate where Home Assistant stores it…

Connecting to HA locally using HTTPS

My set up is very similar to Chris. I can also access my domain remotely. I tried that using cloudflare and it worked. This is what I wrote on deleted post without insulting some guy. You need two addons. Adguard and nginx. First you will create some free domain. I’m using dynu dns. With nginx you can create proxy host and get cert for that domain. How to get ssl cert is explained on their site. In nginx just type domain name you created and use scheme http. For ip address use home assista…

My HA instance is a ‘bare’ install on an old x86 net-PC and works fine apart from this error about untrusted certificate authority on the Android apps (PC browser on Windows and Linux is fine). Until about 6 months ago it just worked fine - period - as it should.
current versions are

• Core2024.12.3
• Supervisor2024.12.3
• Operating System14.0
• Frontend20241127.8

I use http to access HA on my home LAN ONLY - I do not access anything on my LAN from the internet (unless I use Teamviewer to remote in - that works fine) and therefore I do not use https for the various servers available to me within the home (on another PC) e.g. PRTG, XAMPP, Jellyfin, NextPVR etc - they all work fine without having to install certificates etc. (or their install includes them without my knowledge)

from my limited understanding I may have to install a certificate on my Android devices - and yet to do that I appear to need a domain name that I do not have because I am not using the internet (again, if I understand correctly) - not least knowing what domain name to use.

Those many posts above mostly seem to suggest getting a certificate somehow and even the most helpful immediately jump into jargon about how to do so, or assume a particular operating system e.g.Mac They are all above my level of understanding of the issue within the context of HA. Several mention Letsencypt, but I do not understand its relevance. Most of the posts deal with HA that is accessed remotely or where the LAN has other internet connections.

I have looked at my configuration.yaml and I do not have any reference to http or https
If I try and access HA using https it fails
I do not recall any option to use one or the other during install but may have missed it.

I want to continue to use http within my LAN (I understand and agree I should use https if on the internet or accessed from the internet)

I do not need the additional level of complexity (or understanding) to install certificates just to continue to use http on a LAN only system.

However if this is now mandated by HA developers then I think I need a layman’s guide to solving this - I mean really simple, for all install/hardware/OS combinations OR a setting giving the ability to ignore these errors somehow within the companion Android app.

OR I need HA to provide a certificate (maybe within an update) please that I can upload to resolve the situation for HA installs on LAN only scenarios (so can be a duplicate) - without jumping through the relatively complex explanations found or linked from the posts above.

as someone posted elsewhere - I just want to spend time understanding/developing my HA.

Edit:
I looked at changing from http to https

Certificate Authority and self-signed certificate for SSL/TLS

This guide has been migrated from our website and might be outdated. Feel free to edit this guide to update it, and to remove this message after that. If your Home Assistant instance is only accessible from your local network, you can still protect the communication between your browsers and the frontend with SSL/TLS. Let’s Encrypt will only work if you have a DNS entry and remote access is allowed. The solution is to use a self-signed certificate. Please note, however, that after y…

which maybe out of date anyway - Found another reference to Letsencrypt: - it says LetsEncrypt will only work if there is DNS and remote access - I do not have or want remote access.
More recently someone pointed to: howto/HomeAssistant/HomeAssistantTrustedSelfSigned.md at 7c7f9230aa2544f8bf3954261c7094335cb35d9c · ouaibe/howto · GitHub
I tried reading this and quickly got bogged down.

having written this, I am thinking I must have missed something - a mystery post or web page that explains and/or resolves this in which case thanks for reading and please point me in the right direction.

with thanks