When Norton VPN is on and I try to launch thinkorswim, the app gets stuck at Installing Updates and will not launch.
If an app is trying to access the update servers for the developer, it is possible that the web site where the updates are stored is blocking access from known VPN IP addresses. This can be for copyright, legal, or political reasons. There is nothing a VPN provider can do to bypass a web site owner's legal right to protect their content.