Error code:
Rejestrator: homeassistant.helpers.script.pc_marcin
Source: helpers/script.py:1805
PC-MARCIN: Error executing script. Invalid data for call_service at pos 1: Not a valid add-on slug for dictionary value @ data[‘addon’]
Based on: Home Assistant Wake On Lan & Home Assistant RPC Shutdown (HOW-TO) - Kiril Peyanski's Blog
Any idea?
Have you installed " Home Assistant Add-on: RPC Shutdown " ? , or some other RPC Shutdown-Service ?
PS: And don’t expect people would watch a video of how someone else have done something, beside back in 2022( If that matters in this case )
What’s important is, What have you done, step by step !
Switch/turn_off ?
Not a valid add-on slug ?
It’s an official add-on
Changed windows registry, firewall and checked remote services, password set for the admin account.
It doesn’t work on both the switch and the button.
And have you rebooted HA after you installed the Add-On ?
Have you started the add-on ? , anything in the logs of the add-on ?
Seems like it can’t find the add-on
Maybe because you should use under score
addon: core_rpc_shutdown
I’ll check that later
tbh I’m not sure if I need to be logged in with this user
psexec also doesn’t want to execute
C:\Windows\System32>psexec \192.168.1.109 -u .\administrator shutdown /s /f /t 0
Password:
PsExec could not start shutdown on 192.168.1.109:
Login error: The user has not been granted any login type on this computer.
my ‘whoami’ account where I am logged in has no password, only a pin code
Change it Now !, it’s wrong in your config, It Is Underscore
And the Message says " Not a Valid add-on slug(Container-name of the add-on)
Your settings of your windows machine i dont know about, i never use the administrator in my windows machines ( i “save” the for "emergency cases ) 
However to log into my Windows Gui i also use pin ( This i doubt will work for you, you should use your passwd, not your pin , for RPC ) What ever account you try to access it through
That worked, and finally managed to shut down my pc
Therefore, I am replying now 