Chromecast chaos - 2nd gen devices go belly-up as Google struggles to fix certificate issue

Has your old Chromecast suddenly developed a problem?

You're not alone it seems.

Many users of second-generation Chromecast and Chromecast Audio streaming devices have discovered that their beloved dongles have gone belly-up and are showing error messages such as:

"Untrusted device: [name] couldn't be verified. This could be caused by outdated firmware."

And what has the typical tech user learnt over the years if a piece of hardware isn't working properly? Why, do a factory reset of course!

Woah! Stop right there - because Google is advising Chromecast owners to not make the mistake of thinking that performing a factory reset on their Chromecasts will fix the issue.

Indeed, Google goes on to explain that if you perform a factory reset while trying to troubleshoot the issue with your Chromecast, you may find yourself unable to re-setup your device.

Google says it is working on the issue, and will keep users updated via its Nest Community page when it has more to share.

The original "untrusted device" problem appears to be linked to an intermediate Certificate Authority (CA) that expired on Sunday 9 March 2025. When originally issued the certificate was set to expire after ten years and - yup! - it seems no-one at Google has renewed it since the launch of the Chromecast.

This has meant that Google's servers cannot authenticate that older Chromecasts are genuine, and results in the display of the error message.

According to a report in The Verge some Chromecast users have received an apology email from Google for the inconvenience:

We’re contacting you because of a disruption affecting Chromecast (2nd gen) and Chromecast Audio devices. We apologize for the issue and understand your frustration. We are working to roll out a fix as soon as possible and will share updates and guidance on the Nest Community page. We appreciate your patience as we resolve this issue.

I think it's safe to predict that Google should be able to fix the problem, although it may take longer than just a few days. No doubt the lack of a fix will leave some users disgruntled or baffled as to why they are not able to stream their favourite videos and TV shows for the last few days.