Hi there!
Do we understand you correctly that Cassini applications are accessible from an another machine inside the LAN, but not over VPN? It's unclear whether you have only tried reaching the apps from the same box where they are hosted, or you also tried to access it from other machines within the LAN.
In general, we'd recommend focusing on the networking as a potential cause as UltiDev Cassini simply listens on the port, and if port is not blocked by firewalls and TCP traffic is routed properly, Cassini apps should respond on it.
Please take a look at the Windows Event Viewer (Application) to see if there are any relevant errors/warning.
We are definitely interested in helping you figuring out what is going on.
Best regards,
UltiDev Team.
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