Removing about 800GB back up files

I read this:

http://community.norton.com/t5/Norton-360/N360-BACKUP-folder-at-702GB-quot-Delete-backup-files-quot-option/td-p/1044477

And it is not working. I desperately need to removed this massive amount of back up in the N360_BACKUP folder that's been created on my drive. I finally now know why my computer was filling up so fast. What grief!

Can anyone help me? I am having no luck....

thanks....Rob