Hi all, I have a problem to access a Home Assistant app on my smartphone or browser page on PC or same smartphone. The message I get in the app is the following “The home assistant certificate authority is not trusted, please check the home assistant certificate or connection settings and try again.” I hope somebody can help me.
How is your HA exposed to the Internet? Nabu Casa? Do you have any proxies in the way?
Duckdns proxy
Then you have a problem there. Sounds like an invalid or expired certificate.
Do tou use http or https?
If https, what do you use to generate your certificates?
Indeed looks like they expired, and need renewal.
Let’sEncrypt is the commonly used add-on for that.
I used https, but how do I now install and/or update certificates?
I’m using a different approach myself (I run VMWare on a debian host, and I run Apache and Let’sEncrypt on the host and use it as a reverse proxy for HA).
The easiest is to use the Let’sEncrypt add-on on HomeAssistant (assuming you run HAOS),just google it?
Nginx proxy manager also has lets encypt functionality built into the UI. Its super easy to setup and then access all of your homelab services from the internet.
Also, I’m using Uptime Kuma to monitor my availability, and find that duckdns is very poor, with the DNS resolution dropping regularly. Instead, I prefer the dns service offered by afraid.org which has been rock solid and offers the same thing.
Thank you so much for your answers, yours is a great help. Since I no longer have access to either my smartphone or my PC to homeassistant, how could I add and configure new integrations?
On your PC you should be able to access it, just click ‘Advanced’, and click proceed on chrome (or continue on Edge):
I took the screenshot from the phone’s browser
use the ip address, not the dns name 
Unfortunately it’s the same result 
Can you even ping the IP address??
(on what system is your HA running ?)
Ha running in raspberry pi 4. Sorry but I don’t know how ping the IP address
You could connect a monitor to the raspberry and lookup the IP address there?
Once the address is known, open a command prompt on the PC and type:
ping with the IP address you found.
C:\>ping 192.168.1.2
Pinging 192.168.1.2 with 32 bytes of data:
Reply from 192.168.1.2: bytes=32 time=29ms TTL=64
Reply from 192.168.1.2: bytes=32 time=1ms TTL=64
Reply from 192.168.1.2: bytes=32 time=1ms TTL=64
Reply from 192.168.1.2: bytes=32 time=36ms TTL=64
Ping statistics for 192.168.1.2:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 1ms, Maximum = 36ms, Average = 16ms
PS: If your routers MDNS is working properly, you should also be able to use homeassistant.local:
C:\>ping homeassistant.local -4
Pinging homeassistant.local [192.168.1.2] with 32 bytes of data:
Reply from 192.168.1.2: bytes=32 time=3ms TTL=64
Reply from 192.168.1.2: bytes=32 time=3ms TTL=64
Reply from 192.168.1.2: bytes=32 time=38ms TTL=64
Reply from 192.168.1.2: bytes=32 time=1ms TTL=64
Ping statistics for 192.168.1.2:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 1ms, Maximum = 38ms, Average = 11ms
(the -4 forces to ping to use IP4; if ommitted, you might get the IP6 address instead)
I just realize, did you try to open https://homeassistant.local in your browser ?
I try to connect a monitor to raspberry and the message is ‘Error returned from Supervisor: system is not ready with state :setup’
- Is this a new setup?
- If yes, just start-over.
- If not, have you made a backup?
- If you have a backup, secure it.
- Once you have your backup secured, start over and restore from backup…
I have a backup but it’s inside of HA app