Quick Summary

Email quota per account
  • 50 GB for Office 365 users – @connect.ust.hk and @o365.ust.hk
  • 20 GB for staff (Exchange 2013)

NB: Quota includes inbox and all other mail folders. Check your mailbox usage regularly

If quota reached
  • Office 365 users (e.g. @Connect)
    1. Warning issued at 49 GB
    2. Cannot send at 49.5 GB
    3. Cannot send/receive at 50GB
  • Exchange users:
    1. Warning issued when usage exceeds 95% of quota
    2. Cannot send/receive mail when mailbox is 100% full, with senders receiving a bounce back message

NB: Keep monitoring your usage to avoid late delivery of incoming email, and archive older or less frequently used mail.

Maximum size of outgoing message
  • 25 MB for Office 365 users
  • 100 MB among Staff Exchange users
  • 50 MB (server: smtp.ust.hk)
Maximum number of recipients per outgoing message
  • 500 email addresses (Office 365 users)
  • ~250 – 260 (Outlook Users)
  • 300 email addresses (server: smtp.ust.hk)

NB: To email larger numbers of recipients, use the mailing list service.