When you start the Zivver Synctool, the following error appears:

Unable to check supported versions

Your internet connection is working correctly.

Cause

The automatic update of the Zivver root certificate did not start.

Solution

Enable the setting that automatically updates root certificates on the server. Set this registry key:

HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\SystemCertificates\AuthRoot "DisableRootAutoUpdate"=dword:00000000