Resolved Program Files Directory

Hi Folks, this is as much out of interest as desperation.
I'm sure you all have come across some software downloads that do not give you the option of choosing where to instal them they just default to ones 'C' drive, Google Earth being a prime example. This, of course, is not always desirable and I read somewhere that, in XP, it is possible to force the installation onto another drive, in my case 'E' by running Regedit and drilling down HKEY LOCAL M/C > SOFTWARE > MICROSOFT > WINDOWS > CURRENT VERSION and temporarily changing the Prog Files Directory to 'E/Prog Files'.
Has anybody else had success doing this ?, it doesn't seem to work for me.
I tried installing the software straight after making the directory change and also doing a reboot before the attempted installation but no luck.

I apologize if you feel this post should be in another forum, it was a toss up between here and 'Other Software' forum but as I'm talking XP specific I chose this one.

 

Most software has to be installed in the drive that the OS is in or it simply will not work.

 

Okay Folks, thanks for your comments. I'll be guided by you and leave well alone.
Regards