Outlook: Cached Exchange Mode

Cached Exchange Mode allows you to work with your Outlook account data when your connection to the Exchange server is interrupted or unavailable. Cached Exchange Mode stores a copy of your mailbox on your computer by automatically creating and using an offline folder file (an .ost file), into which it downloads and maintains a synchronized copy of the items in all the folders of your mailbox. Outlook automatically manages your server connection and data updates; when your connection is restored, Outlook synchronizes your cached mailbox with your mailbox on the server. However, you still have the option to manually set the connection behavior in order to control the amount of data transmitted to or from the Exchange server.

Note: If you use third-party applications that interface with your Outlook profile (e.g., Outlook add-ins), ITS recommends that you research these applications to make sure they are compatible with Cached Exchange Mode before enabling it.

To enable or disable Cached Exchange Mode:

1. From the File tab, under "Account Information", click Account Settings, and then choose Account Settings... .

    

2. Highlight your Exchange server account, and then click Change... .
   
   
3. To turn Cached Exchange Mode on or off, under "Microsoft Exchange Server:", check or uncheck Cached Exchange Mode. Click Next, and in the window that opens, click OK.
   
   
4. Click Finish. Restart Outlook for the change to take effect.