When connecting to an SSL-enabled site, you may receive one of the following errors:

This error occurs because the server certificate cannot be validated; the certificate issuer is not in the local Windows Trusted Root Certification Authorities store.

KLS Backup uses this certificate store to validate certificates when it connects to an SSL-enabled site.

You can view the list of root certificates by using the certmgr.msc snap-in (for current user certificates) or the certlm.msc snap-in (for local machine certificates), and then navigating to the Trusted Root Certification Authorities node.

The local certificate store does not include every certificate from the Microsoft Trusted Root Program. If you receive a certificate error even though the certificate is valid and the server can be accessed through Chrome or Edge, the local certificate store must be updated to include the required root certificates.

An update to the certificate store can be triggered by accessing the problematic site using Internet Explorer. Although Internet Explorer is no longer included in modern Windows setups, the Microsoft Edge browser still provides an Internet Explorer mode.

To enable Internet Explorer mode in Microsoft Edge, go to Settings, Default Browser and turn on the Allow sites to be reloaded in Internet Explorer mode option.

Example: The well-known Wikipedia site uses the following certificate. If we manually delete the existing root certificate from the local certificate store and then visit the site in Internet Explorer mode, Windows will automatically update the certificate store and download the required root certificate chain.

After the certificate store has been updated successfully, you can disable Internet Explorer mode in Microsoft Edge.