I’d grown spoiled with my MOM pack for Exchange 2003 since I was able to tweak it to alert me (the admin) when a user’s mailbox was being issued size limit warnings.  Several times I was able to catch users stuck with items tucked away out of their view, or the storage of large files that’s better suited to the file server.  After moving to Exchange 2007 though Microsoft removed the event log entry that I used to trigger the MOM condition.  My fix was to create a script that would run on the same schedule as the one used to issue mailbox size warnings.  After combing a variety of pages I came up with the following imperfect, but sufficient script:

function send-email($SmtpServer,$From,$To,$subject,$Body){
$smtp = new-object system.net.mail.smtpClient($SmtpServer)
$mail = new-object System.Net.Mail.MailMessage
$mail.From = $From
$mail.To.Add($To)
$mail.Subject = $subject
$mail.Body = $Body
#$mail.IsBodyHtml = $true
$smtp.Send($mail)
}

get-mailboxstatistics|out-file mstat.txt
get-childitem mstat.txt|select-string -pattern “Issue”|out-file results.txt
$File=get-childitem “results.txt”
$FileContent=get-content “results.txt”
[string]$formattedLength = $file.Length
if($file.Length -gt 5){
send-email email.server.com “server@example.com” “admin@example.com” “Mailbox size alert” $FileContent
}

I apologize for the lack of comments, but what I’m doing is snagging the stats, searching for the word ‘Issue’ to see if a warning or some such was issued, then checking the resulting file size of the search and if it’s oversized (i.e. actually contains something) it’s emailed off to the desired contact.

(UPDATE: this e-mail size alert works for Exchange 2010 as well)

(UPDATE 12/6/2013: this e-mail size alert does not work for Exchange 2013.  I’m working to brew up a solution.)