TLDR: Let's Encrypt's old CA ROOT certificate expires in a week. Your software (and your clients' use of your software) might be affected. If the root ca certificates your SSL-enabled code uses are too old and have not been updated, the SSL client in your code may not work after Sept 30,2021. The "may not" work depends on details in the link below.


The whole page is a good read if this stuff matters to you. The highlighted portion where the link goes to names specific builds etc that can be affected by this.

The question for Friedrich is this: Where do the CA root certs come from that Update/Check SSL uses? The local Windows certificate store?

Thanks in advance,