TLEs are normally retrieved from Taitus servers, from addresses like this
Make sure your firewall is not blocking server 1.software.taitussoftware.com
If TLEs are not updated for too long (> 7 days) , SaVoir will write the satellite name in red.
SaVoir will nevertheless continue using the latest available TLEs for the satellite, but you can expect the accuracy of predictions will be degraded.