This article shows you the steps on how to install the new root certificate – ISRG Root X1 – on your Mac OS device.

1. Download the certificate from this link: http://vo.agnx.com/isrgrootx1.der

2. Once the certificate is downloaded, double click to open it via Keychain Access.

3. When prompted to provide a name and password, type the name and password for an administrator user on this computer. Then, proceed by clicking on [Modify Keychain].

4. The certificate is installed in your Mac OS device.