HI, I've got a 1TB samsung external hard drive set for Time machine for my Imac(Lion) No longer allowing update of Time machine as says set for read only. Been into options etc and cant seem to change it and can also see some files on the hard drive that I'd like to remove as no longer needed but can't delete them as not allowed to. Still got 190GB available. Nervous now as to what to do about the two separate issues. any help would be appreciated!