Hello, Paul.
We learned from TrueCafe that their product installation ships modified version of UltiDev Cassini. That's the reason why upgrade may have broke the application. There are couple of things you can do. If you have good understanding of web hosting, you can use UWS Explore to re-register the application on the same port with "/" virtual directory and use 32-bit host process running under Local System user account. It's probably the easiest way to repair the program.
If that does not work, you may have to uninstall both UWS and our version of Cassini and reinstall TrueCafe to let it install 32-bit of Cassini.
You should also contact TrueCafe support as they might be able to provide better guidance.
Best regards,
UltiDev Team.
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