Server verification failed error from the VPN companion app

This error can be due to obsolete CA lists in your PC.

The following steps show how to fix this issue from a windows PC and using google chrome browser.

1. Use the browser to download the Root CA certificate:
   1. click on the connection detail icon:
      
   2. enter certificate details:
      
   3. select the root certificate - the first one in the hierarchy, for example ISRG Root X1) and click to export to save it to a file:
      
2. Install it in the Local Machine windows certificate store:
   1. double click on the downloaded certificate:
      
   2. install in Local Machine store (the certificate is used by a windows services so it needs to be available at machine level):
      
   3. click on install certificate and follow the guided procedure making sure to install it in the Trusted Root Certification Authorities store
3. reboot the machine.