Suppose you have already used my Synology Wildcard guide to get Home Assistant to work over HTTPS. And today, following the latest Home Assistant update, you’ve found that you can no longer get Reverse Proxy for Home Assistant to work. If you are getting a 400: Bad Request error when you try to access your Home Assistant via HTTPS, then you’re not alone. In today’s article I will teach you how to fix the Home Assistant error and access your Home Assistant over a secure HTTPS connection again!

Note: Check out my new guide on How to Fix 400: Bad Request error on Home Assistant Supervisor

• STEP 1

Please Support My work by Making a Donation.

• STEP 2

Install Text Editor via Synology “Package Center”. (Mandatory STEP.) If you already have Text Editor installed on your Synology NAS, skip this STEP.

• STEP 3

Go to File Station / Docker / homeassistant folder and open the file configuration.yaml Follow the instructions in the image below.

• STEP 4

Copy paste the lines below in the configuration.yaml file. Save the file. Follow the instructions in the image below.

http:
  use_x_forwarded_for: true
  trusted_proxies:
    - 127.0.0.1

• STEP 5

Restart the Home Assistant Container. Right click on the home_assistant container, then click Restart. Follow the instructions in the image below.

• STEP 6

Go back to STEP 1 or you will deal with karma 🙂

• STEP 7

Now you can access your Home Assistant over HTTPS once again if you have correctly set up the Reverse Proxy by following my Wildcard guide.

This post was updated on Friday / September 29th, 2023 at 8:17 PM