Consolidate problem...

Hi, I am trying to consolidate my iTunes library and all files to an external drive as I am running out of space on the current one. When I choose the colsolidate option I am told that there is not enough space on the enternal drive to copy the requested files. This is not the case by a long shot. I have over 700 Gb free on the external drive and the following in my library;

Music 80Gb

Movies 0 - I had to remove these as I was looking for space.

TV 2.6Gb

Podcast 350Mb

Books 12Gb

Apps 0.6Gb

So all told that makes my library about 100Gb and I have 700Gb space and iTunes can't handle this.

I am using the iTunes menu to do this File -> Library -> Consolidate Library and I have changed my library location in the preferences dialog to point to the external location.

Perhaps I am doing something wrong as surely Apple could not have shipped this software with such a huge bug, then again I regularily find bugs in iTunes so perhaps this was never tested. Any which way this is a shocking experience and very poor quality from a company of the size of Apple.