He encontrado la solución, esta en la web de embarcadero, aquí esta el enlace:
lo copio y pego por si desaparece cuando pase un tiempo.
http://edn.embarcadero.com/article/27780
Missing components in Delphi 6.
Question:
Why am I missing components after installing Delphi 6?
Answer:
This most commonly occurs if you had a previous edition of Delphi 6 that you uninstalled. It is possible that there are registry entries left over from that installation because of the new way Delphi is creating the startup registry configuration. It can also occur if you run the stand alone register program or install third party components, which will create the D6 registry key, before actually running Delphi 6 for the first time.
The solution for any of these is to run the utility d6RegClean.exe that comes with Delphi 6, and then restart Delphi before installing anything else. d6RegClean.exe should be located in the bin directory or on the CD.
Also be sure you are not installing two different editions of Delphi 6 on the same machine (such as Personal and Enterprise).