as suggested by SteveWinter
There should be a way for admins to see what mailboxes have msgs in them, extensions and shared. Especially if VMs aren't getting emailed to anywhere there is no way...
I am being told by various G2C people that they do not have a way or report to show which users have full mailbox's that can no longer take messages. I am told that they don't have this report and that is is not on the roadmap for the future.
If this is the case than someone should seriously RE-THINK that decision. This is a very basic function and almost all my customers have asked for it at one time or another.
Get with the program here G2C, this is a basic tool needed by all admins.