Emails are not consistently delivered, appears to be affected by case sensitivity.
General expectation, is that a sent email is consistently deliverable and readable, without requiring guesswork on the recipient's end, and/or requiring that a recipient or sender relog just to effect actual delivery of a message.
I received emails 03:35:00 and 04:35:41, but never saw 03:54:00 until relogging hours later.
/dev/shm/smlogs/log.txt.3:[2016-04-20 03:54:00] [PLAYERMESSAGE] Server(0) Handle Received PlayerMessage: PlayerMessage [from=Sachys, to=erthparadine, sent=1461124434914, read=false, message=tell me when you get this - its now near 5am here, and im pretty sure you'll have to relog to get it - ive just given you the system co-ords and command for revoking., topic=RE: Faction Points]
/dev/shm/smlogs/log.txt.3:[2016-04-20 03:35:00] [PLAYERMESSAGE] Server(0) Received PlayerMessage: PlayerMessage [from=erthparadine, to=sachys, sent=1461111563868, read=true, message=That's odd. Mail is working fine for me. I'll check for errors in the logs. Let me know if you're getting any error messages too., topic=RE: Faction Points]
/dev/shm/smlogs/log.txt.1:[2016-04-20 04:35:41] [PLAYERMESSAGE] Server(0) Received PlayerMessage: PlayerMessage [from=Sachys, to=erthparadine, sent=1461126936423, read=false, message=i already told you that - it wont associate you dmin and player accounts, tells me youre offline half the time - and that is on a reply - not a direct typed message, topic=RE: Faction Points]