After installing DT in my Vista 64 Ultimate, I get the following error after rebooting.

Initialization error 0. This program requires at least Windows 2000 with SPTD or higher. Kernal debugger must be deactivated
I have tried uninstalling DT and manually installing SPTD 1.56 again. But now I get a new error that says this:

Internal setup error. Error code: 14. Contact Support.
I tried cleaning the registry of all DT related and it hasn't helped.

I really need some help here