"It's not possible to set up arbitrary email accounts in exchange server...? You know..... for testing...?"
I'm sure it is possible, but there are far too many caveats to want to do so. First, in order to trigger this, you need to set up five thousand such accounts. I don't know whether it's possible to run a batch setup process for that many accounts and then run a batch delete once testing is completed, but if it is at all painful I'd choose not to. Second, having that many test accounts puts a strain on resources. Five thousand mailboxes would take up a lot of disk space, whereas five thousand aliases going to the same place might not be counted as separate recipients for testing. Third, at least some systems are charged per mailbox, meaning you would pay a healthy sum for the privilege of testing.
Biting the hand that feeds IT
