I asked everyone today to empty out their frequent contacts folder because they all got clogged with bogus entries that did nothing but cause a flood of undeliverable notifications over the past few months. I performed an email upgrade that solved this problem.

So the first two individuals duly delete the contents of their frequent contacts, then proceed to yell at me because all of their addresses have been deleted!

Ummm,

a) you deleted the messages, you didn't have to, and you could have asked me first if you weren't sure,
b) the software warns you that this is an irrevokable action, and there is no going back.
c) the frequent contacts is not your permanent email address book, its only temporary storage for automatically recorded addresses