OK I can look into that, but there must be a table somewhere, I’ll do some searching now that I know what I’m looking for. Then I’ll look to setup zero teir. Thanks.
I’m suffering the forgotten key as well, using esphome 2025.2.2 tried a few things as suggested in various links to this issue but nothing helped so far. There is still this api connection problem. I’ now going to reinstall the esp rather that update via esphome run xxx.yaml
Problem solved: copied the existing “xxx.yaml” into “yyy.yaml” and changed the name under esphome in this file
Actions:
mv xxx.yaml yyy.yaml
vi yyy.yaml
esphome run yyy.yaml
Now removed the old esp device and loaded the renamed one into HA plus setting the encryption key once.
Problem did never turn up again.
a version of this worked for me.
circumstances:
- attempt to integrate apollo msr-1 sensors originally set up with a different ha instance
- sensors connected to same network as ha, so discovered in both esphome and in ha
- took control of sensors in esphome, restarted ha, tried adding in ha, keys invalid
what worked for me:
- deleted all sensors from esphome
- ran search in studio code server for text strings found in sensor names; yaml files for sensors were in esphome archive directory/folder
- deleted all files/entries for sensors in archive
- restarted ha
- took control of sensor 1 in esphome and installed wirelessly
- clicked edit on sensor, cut key, replaced with !secret msr1_key1
- pasted key into secrets and saved
- restarted ha
- clicked to add sensor 1 in ha-- sensor 1 added without requesting encryption key
- repeated for remaining sensors
It appears even celebs/royalty have issues with IoT from time to time, so now I don’t feel quite as bad as I always do when resorting to come here for help 
I just labored under troubleshooting this issue. My advice? Make sure your home assistant installation is not 6 months old. After upgrading to 2025.11, the issue resolved itself.