Quiktime problem

A slightly different Quick Time problem here. Looking for any help. Can not now install Quick time, stand alone or bundled because: “a newer version of quick time has bas been detected…whatever” Not true have tried all googled and Apple instructions to clean/remove previous,including manual though the registry.Removed quick time alternative/and or lite too.Still can not find problem, may be installer but not sure. Do not wish to reformat 300gb+ files on hard drive “C” of XP PRO SP3. Also have done cc, defrag, reboot, removed all Apple and Bonjour and quick time Software and files that I can find in program files and applications etc.Must be possible I would think?