"It is no longer on my hard drive."
Translation:Il n'est plus dans mon disque dur.
Negatives come in 2 words: "ne" + pas OR plus OR jamais OR personne OR rien OR aucun...
You may consider those 2 words as:
- ne pas = not
- ne plus = no more, not anymore, no longer, not any longer
- ne jamais = not ever, never
- ne personne = not anyone, no one, not anybody, nobody
- ne rien = not anything, nothing
- ne aucun(e) = not one, none
Ce n'est pas : it's not Ce n'est plus : it's no longer / not anymore
Hope it helps
Because "il" as a personal pronoun, represents a precise thing mentioned before. This thing is masculine singular, for example "le document".
"Ce" would be used to represent a whole situation, which is less likely in this context of "being no longer in my hard drive".