Define Storage Limits

You can define storage limits for the mailbox. Storage limits include maximum mailbox size and deleted item retention.
  1. Right-click a user.
  2. On the shortcut menu, click Properties.
  3. On the Exchange General tab, click Storage Limits.
  4. Under Storage limits, select the Use information store defaults check box to use the default storage limit settings for the Exchange private information store, or click to clear the Use information store defaults check box to change storage limit size thresholds for issuing warnings and prohibitions. If you clear this check box, you can change the following settings:
  5. Under Deleted item retention, select the Use retention time defaults check box to use the default limit settings in the Exchange private information store, or click to clear the Use retention time defaults check box to override the private information store storage limit. If you clear this check box, you can change the following settings:
  6. Click OK to save settings.