Are you using different versions of TurboActivate? Always use the latest version of TurboActivate. And don't mix & match versions of TurboActivate.exe and TurboActivate.dll. Make sure they're the same version.
To fix things, in your app call "Deactivate(true)" that will clear out the activation and remove the product key. Also, instead of using the TurboActivate wizard, try passing a new key using the CheckAndSavePKey() function. What happens? What happens when you run "Activate()"?
Also, make sure the same TurboActivate.dat is being used everywhere. It sounds like you might have TurboActivate.dats from separate products or versions and one version is activated while the other isn't.