We have not removed some old ones but need to automatically work out which users have not logged in for a while i.e. they are dead users.
It just occurred to me that it must be tough working environment to have a bunch of "dead users" lying around.
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And you might think I'm kidding when I say that in a couple of systems I work on I see a lot of logs complaining about "Zombie Phones".
But seriously, I'm sorry we couldn't come up with a better solution for you.
Perhaps you could capture your SMDR and see what extensions are making out bound calls.
Ralph