vim /mnt/hdb6/boot/grub/menu.lst,,,,,,,,,,,,,,,,,,,,,,,it did work,,,

nedit /mnt/hdb6/boot/grub/menu.lst,,,,,,,,,,,,,,,,,,,,,,,it did work as well.
Yes I can read it,,,but today I realized that I can not modify it,,,,what should I do to overcome this issue ?