1.Exchange System Manager.
2.Locate the specific mailbox store that you want to define storage limits for.
3.Access the properties of the mailbox store.
4.Click the Limit tab.
5.Define the desired storage limit settings for the mailbox store using the following:
•Enable the Issue Warning At (KB): checkbox and specify the appropriate value for the option.
•Enable the Prohibit Send At (KB): checkbox and then specify the desired value for the option.
•Enable the Prohibit Send And Receive At (KB): checkbox and set the appropriate value for the option.
6.Specify when Exchange Server 2003 should send warnings to mailboxes which have reached storage limits.
7.Define the desired deletion settings for the mailbox store using the following textboxes:
•Keep deleted items for (days)
•Keep deleted mailboxes for (days)
8.Click OK.

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