Ensure that TCP/IP is enabled on the SQL server and correct port is specified in Safeguard.
This can be validated from the SQL server. In SQL Server Configuration Manager, expand "SQL Server Network Configuration", select "Protocols for instancename". Ensure TCP/IP is enabled, go to the "IP Addressess" tab and validate the "TCP Dynamic Ports" under IPAll. This port should be used in Safeguard. If any changes are made restart the SQL instance service.