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Outlook for Mac 2011 Best Practices


In response to performance and other problems reported by some Central Exchange users who utilize Microsoft Outlook for Mac 2011 to access their Exchange mailboxes, ACNS reached out to Microsoft and other universities using Exchange or Office 365 regarding recommended best practices for Outlook for Mac 2011. That effort resulted in the recommendations below. Note that these recommendations only apply to Outlook for Mac 2011 and do not apply to people who use Microsoft Outlook running on a Microsoft Windows PC or for users who utilize Outlook Web App ( to access Central Exchange.

Summary of Best Practices

  • Do not mix and match connecting to your Exchange mailbox using Outlook 2011 for Mac (at work, for example) and then use Outlook running on a PC from another location (such as your home).
  • It is strongly recommended to store no more than 5,000 items in a particular folder within Outlook for Mac 2011. This is especially true for Exchange system folders including the Inbox, Calendar, Tasks, Sent Items, and Deleted Items folders.
  • If you create additional folders (referred to as custom folders) or subfolders as a means to organize your mailbox, it is best to create folders at the same level as the Inbox, Sent Items, etc. rather than as subfolders "underneath" one of the system folders mentioned. This is most easily accomplished using Outlook Web App by right-clicking (or Ctrl+click on a Mac) your name as it appears in OWA and choosing the Create New Folder... option, as pictured below. It is okay to create subfolders within a custom folder, but it is recommended that you do not create more than 3 levels of folders - i.e. (1) The custom folder itself > (2) A subfolder under the custom folder > (3) A sub-folder within the subfolder.

    Create folder using OWA

Tips for Re-Organizing a Mailbox

If you have questions about the process of re-organizing your Exchange mailbox using any of the methods below, please contact your local IT support or e-mail the Exchange Help Desk at

  • Particularly in instances where you have large amounts of e-mail to move, the ideal scenario would be to connect an Outlook 2013 or Outlook 2010 client on a Windows PC to your mailbox not in cached mode. In doing so you establish a direct connection to your mailbox on the Exchange server, and you can then commence to creating new folders and moving mail to those folders. Even when using Outlook on a PC, it is best to move mail in batches and to let each move operation (whether it involves moving a folder or a group of e-mails) complete before initiating the next move. In some cases, it may be helpful to create a rule in Outlook that identifies a grouping of e-mail you want to move. For example, you could create a rule (Home tab > Rules button) and set parameters such that if e-mail was received between January 1, 2013-February 1, 2013, move it to a folder named '2013 January'. Once created, you can manually run the rule so that it applies to existing e-mail. After it completes, you can modify the same rule for a different time period and re-run it.
  • Outlook Web App ( is a good tool for creating new folders and for moving folders within your mailbox. The same not does not hold true for moving a large number of items, such as individual e-mails, from one folder to another due to limitations with the number of e-mails you can select at a time from Outlook Web App.
  • If you do use Outlook for Mac 2011 to move multiple e-mails to a new folder or subfolder, again follow the guidance where you initiate moving a batch of selected e-mails and let that process complete before moving another batch of e-mail.
  • The post at (also included in the references section below) is a very good resource for information regarding the use of Outlook for Mac 2011, as well as for ideas on how to sort and move items to comply with the less than 5,000 items per folder concept.