Originally Posted by BWestOz
If the problem arises from using a USB HD you could try using a USB stick instead.
You can put a linux install ISO onto a USB stick with a utility like Rufus.
Have you created some room on the W7 drive? Be sure not to damage your W7 partition.
You could install onto a virtual machine instead (eg Virtual Box).
Hope that helps
Thanks for the reply, I resolved the issue by installing to an external USB hard drive. Everything is working well now. Will eventually format my internal hard drive to remove Windows 7 and install Ubuntu there when I get all my data files backed up.