Some reported problems with old network licenses can be resolved by updating your local license server to Network Licence Manager v2 (2008). This is solely for legacy Ecotect 5.X licenses, not the Autodesk Flex licensing that started with Ecotect 2009, so it will work fine with all your existing SQU1 licenses.

The Ecotect legacy license server has moved. It is still ecotect.com but the IP address it resolves to is now 132.188.65.205. You may need to update your firewall rules if your company restricts external internet access.