Due to a change in certificates, older macOS versions (10.14 and before) currently have issues reaching the servers of our licensing provider. While waiting for Apple to roll out a fix you should be able to remove the expired certificate with the following commands:

cd ~
curl -kO https://letsencrypt.org/certs/isrgrootx1.pem
curl -kO https://letsencrypt.org/certs/isrg-root-x2.pem
sudo security add-trusted-cert -d -r trustRoot -k “/Library/Keychains/System.keychain” “isrgrootx1.pem”
sudo security add-trusted-cert -d -r trustRoot -k “/Library/Keychains/System.keychain” “isrg-root-x2.pem”

Please make sure to copy and paste all lines in your terminal, press enter and provide your password when prompted.

If this does not fix it yet you might to remove the old certificate with:

sudo echo “” && curl -s https://gist.githubusercontent.com/cbenhagen/fe8ed84911b32103e1de80a489c803ea/raw/91be436650e0198dab18a590d1cb9dc132a69e79/cert.pem.diff | sudo patch -Nb /etc/ssl/cert.pem

Newer macOS versions are not affected by this. If all your drivers and other software permit, you could also update to macOS 10.15 and above.