Can't add Vicare integration, Invalid authentication error, but in viessmann site this credentials work

[nurzod]

The problem

Can't add Vicare integration, "Invalid authentication" error, but in (https://app.developer.viessmann-climatesolutions.com/) site my credentials work, i have client_id

What version of Home Assistant Core has the issue?

2025.11

What was the last working version of Home Assistant Core?

2025.11

What type of installation are you running?

Home Assistant Container

Integration causing the issue

Viessmann ViCare

Link to integration documentation on our website

https://www.home-assistant.io/integrations/vicare/

Diagnostics information

No response

Example YAML snippet

Anything in the logs that might be useful for us?

Additional information

No response

[home-assistant]

Hey there @CFenner, mind taking a look at this issue as it has been labeled with an integration (vicare) you are listed as a code owner for? Thanks!

Code owner commands

Code owners of vicare can trigger bot actions by commenting:

• @home-assistant close Closes the issue.
• @home-assistant rename Awesome new title Renames the issue.
• @home-assistant reopen Reopen the issue.
• @home-assistant unassign vicare Removes the current integration label and assignees on the issue, add the integration domain after the command.
• @home-assistant add-label needs-more-information Add a label (needs-more-information, problem in dependency, problem in custom component) to the issue.
• @home-assistant remove-label needs-more-information Remove a label (needs-more-information, problem in dependency, problem in custom component) on the issue.

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vicare documentation
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[Mnovu]

Hi,
I have the same issue. Somehow Viessmann forgets the Access Token if I generate one. Tried it now 4 days in a row, but always the same error. Viessmann plans and maintenance on the 12.11.25 - hopefully this will get fixed?

[CFenner]

@Mnovu

Somehow Viessmann forgets the Access Token if I generate one.

You do not need to generate one, HA integration will request that automatically, you need to provide the clientID. If you handing in the token, you are doing wrong!

[nurzod]

@Mnovu

Somehow Viessmann forgets the Access Token if I generate one.

You do not need to generate one, HA integration will request that automatically, you need to provide the clientID. If you handing in the token, you are doing wrong!

What should I do in my case? I configured the client_id as described on your website.

[CFenner]

Could be the case that you still have a custom component installed.

Install the VSCode add-on an have a look at the config/custom_components/vicare folder. If it is there, delete it.

[steveizzle]

I am having the same issue. Basically it just stopped working some days ago and I tried to reenable it but also get an authentication error..

Before I disabled it I downloaded the diagnostics file and there I found an error which says

"data": [
      {
        "errorType": "GONE",
        "extendedPayload": {
          "replacement": "GET /iot/v2/features/installations/{installationId}/gateways/{gatewaySerial}/devices/{deviceId}/features",
          "sunsetDate": "2025-10-31T12:00:00.000Z"
        },
        "message": "This endpoint has been deprecated and is no longer available. Sunset date: 2025-10-31T12:00:00.000Z Replacement: GET /iot/v2/features/installations/{installationId}/gateways/{gatewaySerial}/devices/{deviceId}/features",
        "statusCode": 410,
        "viErrorId": "req-dc413f64f2e140faaf34cc46fef2ec26"
      },

Maybe that helps