Exporting windows Mail errors

Hi I am having trouble exporting my Windows Mail messages in vista. I had no problems with contacts or anything else, only the messages. I am trying to export them to an external hard drive with plenty of space. There are about 39,000 messages (450 or so MB) but when I go to use the export feature> select >Windows Mail > select all folders > destination (my hard drive) it gives me an error message saying there is not enough file space....or some other message saying some files need to be cleaned, etc., etc.

my hard drive is definitely big enough. And when I choose to export the files locally (to my C:, there are no problems).

However, if I try to manually transfer those locally saved Windows Mail files to my hard drive, it gives me a time frame of 60 or 70 DAYS!. I can't figure this thing out.

I just need to export my messages. Please any help would be greatly appreciated.

J