I correspond with a lot of people and my email program remembers them all. Every time I type in the first few letters of an address, Thunderbird suggests a list of people it thinks I might want to write to. The software of course knows nothing about what goes on in the world around it, and so blithely continues to suggest the addresses even of people who have died.
I have heard of ghost email that has been sitting in some screwed-up mail server for months and only reached its adressee after the death of the person who wrote it. But this is something else. My computer wants me to write letters to dead people.