Managing Your Exchange Mailbox

You may have received a system notification stating that the size of your mailbox is approaching its capacity. This is not something to worry about immediately. This is Exchange's way of giving you a heads up and some lead time to manage your mail before you experience enforcement of the mailbox quota. This article is intended to provide some tips on how manage your email.

Mailbox Quotas Explained

Why is there a quota?

Mailbox quotas are enforced in order to ensure that the University's mail servers run at peak performance levels. This requires that the available disk storage is not allowed to fill beyond capacity. If quotas were not enforced, the storage would completely fill with email and would cause the system to fail. Mailbox quotas were determined prior to the migration of Faculty, Staff, and Student mailboxes. These quota sizes were determined based on the number of users on the system, the average size of mailboxes, and anticipated growth of the institution.

Quota Sizes and Actions - What do they Mean?

Mailbox quota sizes for Faculty and Staff are as follows:

Warn: 850 MB - When your mailbox size reaches 850 MB, the system will send you a notification. This is a reminder that it would be a good idea to start managing your mailbox to reduce its size. At this time no action is being taken on your mailbox, other than sending an automated notification.

Prohibit Send: 950 MB - When your mailbox reaches 950 MB, you will be prevented from sending email. You may not notice this immediately. Messages sent will remain in your outbox pending a reduction in size of your mailbox below 950 MB. You would have to increase the size of your mailbox by 100 MB after you received the notification message before sending is prohibited. At this time you would still be receiving email.

Prohibit Send and Receive: 1 GB - When your mailbox reaches 1 GB in size, you are prevented from sending or receiving email until you reduced the size of your mailbox. Users sending email to you will receive a non-deliverable message from the server and your email will be refused. An additional 150 MB of email have accumulated in your mailbox since the warning notification to have reached this point.

 Student mailboxes have quota sizes of 200 MB, 250 MB and 300 MB, respectively. Many of the following management tips apply only to faculty and staff mailboxes, not student mailboxes.

How do I know how big My Mailbox is?

First, you should be aware that the size of your mailbox is the sum total of all folders, including the Inbox, and all subfolders. This means the sent items, deleted Items (Recycle Bin) and Recoverable Deleted Items. Deleted Items and Recoverable Deleted Items are often overlooked when one does spring cleaning on their mailbox

Determining the Size of Your Mailbox

Right Click the Inbox in the folders list, Access Properties, Click the Folder Size button:

Note the Total size (including subfolders) statistic. This is given in Kilobytes, not Megabytes. Move the decimal point three places to the left to convert and determine the size in MB. Example shown below:
The size of this mailbox is approximately 96 MB in size.

Deleted Items and Retention of Deleted items Explained - a popular misconception

The Deleted Items Folder contains email you have deleted (obviously). A popular misconception is that when you delete email messages they are immediately "gone". They are not. When you delete an email message in outlook it is relocated to the Deleted Items Folder

Email messages in the Deleted Items folder remain here until the folder is emptied. Without emptying the Deleted Items Folder, this is not much different than simply moving a message to a different folder.

Recoverable Deleted Items

Did you know that you can recover items emptied from the Deleted Items folder for ten days?

This is intended to provide users an opportunity to restore email messages deleted accidentally to be restored without the assistance of IT staff. This feature is not widely known and can be both a blessing and a curse when quota enforcement becomes an issue. These recoverable deleted items count against the sum total of your email messages even though they have been 'deleted'. Since they are still recoverable, they still exist and have not yet been purged from the system.

You have reached your quota, what can you do?

Get rid of non-useful email messages

  1. Delete any un-necessary email items. Information has a useful lifespan, and some messages do not deserve to be archived. Cake announcements from 2006 should be deleted. Follow suit by emptying the Deleted Items folder.
  2. Purge the recoverable deleted items. This important step is most often overlooked. Remember that your email messages emptied from the recycle bin remain recoverable for ten days and are counting negatively against your quota. Do the following to purge recoverable deleted items: Select the Deleted Items in the folders list. Click Tools -> Recover Deleted Items

Select all the messages and permanently delete them:

Create an Email Archive

When you have a need archive email messages, you may wish to contact the Help Services Team to assist you with creating the email archive. The process is a simple one where a data file is added your outlook profile for the purpose of holding email. The ideal location is the local hard drive on your computer.

Decide on a Strategy for Archiving

The best approach is to keep it simple. Adopt a broad approach which will make it easy to locate all the messages you want to relocate; example - I only need to keep about a year's worth of mail in my inbox - Sort your messages by date and select all those before a determined date, then move them to the archive. Needs vary for the individual user, but the more general the approach, the simpler and faster it is to archive.

Check the Size of Your Mailbox

Use the Folder Size button on the Inbox folder properties to keep checking the size of your mailbox after archiving and deleting email to determine whether you are now under the quota settings. If your mailbox is still over the size limit, repeat the process and check again.

Contact the Help Services Team

You should not hesitate to contact the Help Service Team if you require assistance with archiving your email or explaining any of the information contained in this document. They are here to assist you.

Strategies for keeping your Mailbox Smaller

Configure Deleted Items to empty upon exiting

This setting is single handedly the most useful at keeping your mailbox smaller. When you close outlook, the recycle bin is emptied. Keep in mind you still have ten days to recover accidentally deleted messages. You can set this by accessing the Tools menu item -> Options and clicking the Other tab as shown below:

Configure a Rule for Sent Items

Outlook keeps a copy of every message you send by default. You may determine that you really only need to keep a copy of messages sent to certain recipients or groups. You can turn off saving a copy of each and every email by accessing the Tools menu -> Options -> Preferences -> Email Options button. Uncheck the box:

Use the Rules Wizard to create a rule to save a copy in Sent Items to select recipients.

Maintain your Mailbox Regularly

Use a simple strategy for regularly archive messages; i.e. at the first of the month, sort the sent items folder by date and archive last month's sent items. Delete messages regularly and save large attachments and then delete them from the message if you need to keep the message.


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