Dear All,
Thanks for the postings.
Well after a certain amount of distress I am pleased to say that I now have CAM working (with 16.2).
I am running Win XP sp3 on a Pentium 4 "own build" machine.
Okay, problems....
1. After failed CAM install, go and find Microsoft's "Windows Installer CleanUp Utility", run and remove the TurboCAD CAM entry
ONLY.
2. Close all programs and turn OFF antivirus software.
3. Run CAM install software.
4. Discover that the download was wrong, was sent link to v14 CAM not V16 CAM software.
5. Turn AV back ON!
6. Send help email to supplier.
7. Get prompt response and a new link a while later (which I pick up the next evening).
8. Close all programs and turn OFF antivirus software.
9. Run CAM install software.
10. Eureka, it installs

11. Turn AV back ON!
12. Run TC16 - 2.5D CAM logo flashes up during start-up - promising.
13. Yes, it works.
14. Try to remember what to do next

Um, decide to wait until weekend and have a proper session.
15. ... Remember to post this update on TurboCAD Forum
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Well, that's a relief.
Best wishes,
Susan.