Biasci, Laura wrote, in part:
>           1 05/09 05/09 Yvonne XXXXXX <[log in to unmask]>
>                         Last error: 5.1.1 No such local user

Laura,

It may mean that those 42 no longer have e-mail accounts.  It may also
mean that this form of their e-mail address is no longer being accepted.
  For example, perhaps "admin.usf.edu" *was* an appropriate domain (or
at least worked), but now all e-mail uses (only) the "@usf.edu" domain?

It sounds like you need a quick chat with [log in to unmask] (or perhaps
[log in to unmask]).  Hope this helps!

cheers, wayne