Pinnacle studio not enough space

I have installed Pinnacle studio 10.5 on my computer and when I try to run the program I get a message that Pinnacle needs 500MB of space to run and I only have 255 MB of space.I have tried removing old programs and defrag but still do not have enough space.I have an external hard drive can I use the space on that in some way to solve my problem.Any help would be appreciated as I am a bit of a computer thicko!

Its ok the penny has dropped ,my computer has only got 256 Ram and pinnacle requires 512 Ram, I think