Mailbox Management

What are the mailbox quotas?

Each mailbox can use up to 1 GB of space on the server. The system performs a check at 2am each day and sends a message to any mailboxes that exceed one of the following limits at that time.

  • 900 Megabytes - issue warning
  • 920 Megabytes - prohibit send
  • 1024 Megabytes (1 Gigabyte) - prohibit send and receive.

The limits are set to make you aware that your mailbox is becoming too large, before you are unable to receive messages.
If your mailbox size exceeds one of the limits after the check at 2am is performed, you will not receive a warning message, but you may be unable to send or receive emails until you reduce your mailbox size.

How do I keep the size of my mailbox under control?

You need to do some housekeeping periodically to keep the size of your mailbox under control.  Response times from the server will also be improved if you keep the number of items in your main folders such as the inbox, sent items and calendar to a minimum. Try to file messages that you need to keep in subfolders within your inbox and periodically delete or archive older items.

A mailbox cleanup tool is included in Outlook 2010.  This can be used to check the size of your mailbox and deleted items folder, and identify old or over-sized items.

To access the tool from Outlook 2010: on the File tab, click Cleanup Tools and then click Mailbox Cleanup.

Items in all folders contribute to the total size of your mailbox, including the deleted items, sent items and inbox subfolders.

Messages with large attachments often consume more space in your mailbox than several hundred standard messages.

Messages will remain in your Deleted Items folder until you empty it or permanently delete the messages from it.

It may be necessary to archive older items if you need to keep them.  Information on doing this can be found at the links below.  Note that archived messages are stored on the local disk of your machine.  You are responsible for backing up this information for restoration purposes in the event of a hardware failure.

Outlook 2010