When you install programs, registry entries will be created.
That's how the program knows whether you have installed it before
and thus preventing you from reinstalling it again. You have to
delete registry entries related to them and install it again. This
is risky as registry entries are created everywhere for the
program. Delete wrongly and that's it.
Spyware Doctor version maybe the same all the time, but the build
number is different. That's how they defend themselves against
crackers. You have to find the crack with the correct version and
build number for it to work. However, to prevent successful
registration of cracked programs, the makers of Spyware Doctor has
cleverly used anti-spyware definitions to defeat cracked softwares.
Any softwares that have been cracked and attempts to update, will
either fail or update successfully, but will return to the same old
trial program after updating definitions.
