Why won't Ubuntu let me copy things?

[said99]

My Windows PC stopped working for some reason, so I made a Ubuntu disc and have been running it from that. However I want to reformat my PC and get Windows back, but when I try to copy things from the "Users" folder on my hard drive to my external hard drive it says(I'm using the folder Sample Music as an example): "Error while copying" "There was an error getting information about the files in the folder "Sample Music" Error stating file '/media/HP/Users/Public/Music/Sample Music/AlbumArtSmall.jpg':Input/output error". The external hard drive works fine and has way more free space then I need to copy this stuff, but it does this with pretty much everything I try to copy to it. Copying stuff to the hard drive works fine on my other PC, so it's not the hard drive, It's Ubuntu. I don't have permission to copy this stuff or something. When I write click on a folder and go to Properties and then to Permissions, if I change the "File Access" thing, it just goes right back to nothing. How can I copy this stuff? I'm new to Ubuntu so assume I know nothing about it. Is there some command I can do to disable the protection or something? Thanks!