When I hover the mouse over the warning icon in the Manage Accounts section (see image attachment) it seems to say the opposite thing that it should. I believe it should say "...is NOT associated..." instead because there are no email accounts for those mantis accounts. If this is oncorrect, please explain what the tooltip text means then.
Tbe tooltip is right, it's telling that there are mutiple users using the same (empty in your case) email address.
It's questionable, if this warning should occur for emtpy email addresses.
If you don't need unique email addresses at all and want allow your users to use the same email address for multiple accounts, you could add the following line to config_inc.php and get rid of the warnigs and the tooltips-
Okay, I guess that makes sense. These are all user accounts from *former* employees, since we don't get notified when someone leaves all of these phantom accounts get left in Mantis...thus my other email asking if there is a way to do a mass select & delete of users. There are a couple of pages of accounts and I don't want to go through them one-by-one...