The usual cause for this is the customer's firewall, or other security measures. Though it is possible that the customer's internet may be down and they haven't noticed.


Have the customer check that ports 1268 and 1433 are both enabled for outbound traffic. Also ensure that these are added into internet options: https://*, https://*, and https://* . Finally if the customer blocks encrypted keys: they will need to add us as an Encrypted Key Exception.

If that is all correct and they still cannot connect, then ask for help.