Let's Encrypt Expires Root Certificate, Many Devices and

This guide provides a clear, practical overview of let's encrypt expires root certificate, many devices and, with useful context, important details, and straightforward takeaways for everyday readers.

On September 30, 2021, Let's Encrypt's DST Root CA X3 root certificate expired and had to be replaced with a new one. The newly applied certificate is ISRG Root X1. This has caused access issues for a wide range of devices and websites globally. Free SSL sites, legacy devices, and iOS devices are most affected.

As announced by the company that owns the Let's Encrypt service, in most cases your system will automatically switch to the new certificate-based authentication chain. However, sometimes the expiration of the root certificate causes the certificates to be deemed untrusted or invalid.

To fix it, you need to make sure that the server (for admin) and device (for users) use the correct authentication string.

For sites that use free SSL, the admin can consider a new SSL alternative. After replacing the new SSL, the clients have to restart to be able to access the site.

Good luck with your fix!