On Sept 30th, 2021, the root certificate DST Root CA X3 from Let's Encrypts expired. It has been replaced with the ISRG Root X1 certificate.
If you cannot open https://clideo.com or other websites on 10.11 or older macOS, you might need to update to a newer macOS version or install the trusted root certificate yourself.
Install the trusted root certificate on macOS
For older macOS (10.11 (El Capitan and older)), do the following:
- Go to http://x1.i.lencr.org/ to download the ISRG Root X1 certificate file.
- Open the Keychain Access app and drag the certificate file into the System folder of that app.
- In System, double click ISRG Root X1 certificate, select Trust and change Use System Defaults to Always Trust. Close the app and confirm the change with your password (if prompted).