How to use offline folders in Outlook 2002

For a Microsoft Outlook 2000 (CW) version of this article, see
195435 .
For a Microsoft Outlook 98 (CW) version of this article, see
182158 .
For a Microsoft Outlook 97 version of this article, see
161725 .


When you use Microsoft Outlook with the Microsoft Exchange Server Information Service, you can work with folders "offline;" that is, you can use the contents of a folder without a network connection. This article discusses how you can create, use, and synchronize offline folders.

More Information

Offline folders are the quickest and easiest way to work offline with Exchange Server. Offline folders make it possible to work with the contents of an Exchange Server folder while you are not connected to the network (offline), and then when you are connected to the network, synchronize the folders.

Offline folders are stored in an offline folder (.ost) file; the default location for the .ost file on Microsoft Windows 2000 is your current Documents and Settings/username\Local Settings\Application Data\Microsoft\Outlook folder, or Windows\Local Settings\Application Data\Microsoft\Outlook on Microsoft Windows 98. Like personal folders (.pst) files, the .ost file can be compacted to save space on your computer.

The difference between an offline folder file and a set of personal folders is that the offline folder file starts as a mirror image of your folders on the Exchange Server computer, and is updated by the server during synchronization. A set of personal folders, on the other hand, is simply a storage location on your hard disk or a server other than the Exchange Server computer.

When you are working offline, you work with the contents of an offline folder exactly as you do with a folder that is on a server. For example, you can change and move items in your offline Inbox, send messages that are placed in your offline Outbox, and read your offline public folders. You will continue to receive new messages in your online mailbox. However, you will not be aware of these changes on the server until you connect to the network.

When you need to update the contents of the offline folder, you synchronize the folder with the server, and then continue to work offline. The Synchronize command connects to the server through Dial-Up Networking, copies the changes made, and then disconnects. Any item that you delete from either the offline folder or the corresponding server folder is deleted from both folders after synchronization occurs.

How to Create an Offline Folder File

To create an offline folder file, follow these steps:
  1. On the Tools menu, click E-mail Accounts, click View or change existing mail accounts, and then click Next.
  2. In the Outlook processes email for these accounts in the following order box, click Microsoft Exchange Server, and then click Change.
  3. Click More Settings.
  4. Click the Advanced tab, and then click Offline Folder File Settings.
  5. In the File box, type the path to the file that you want to use as the .ost file and then click OK. The default name is Outlook.ost. If this file already exists, you will receive a prompt for a new name.

    If you receive the message below, click OK:

    <path><filename>.ost could not be found. Would you like to create it?

    <path> represents the path to the ost file and
    <filename> represents the name of the ost file.
  6. Click OK, Next, and then click Finish.

How to Set Which Folders Are Available Offline

The Inbox, Outbox, Deleted Items, Sent Items, Calendar, Contacts, Tasks, Journal, Notes, and Drafts folders are automatically available offline when you set up offline folders. To use any other folder offline, you must specifically set it for offline use. To do so:
  1. On the Tools menu, point to Send/Receive Settings, and then click Define Send/Receive Groups.
  2. In the list, click a Send/Receive group containing an Exchange Server account, and then click Edit.
  3. Under Accounts, click your Exchange Server account.
  4. In the list, select the folders that you want to use offline in addition to your default folders.

    If you want to apply a filter to a specific folder, click the folder, click Filter Selected Folder, and then select the options that you want.

    If you want to limit the size of messages to download when you synchronize folders, click Limit Message Size, and then click the options that you want.
  5. Click OK.
NOTE: The offline folder file settings may not be available. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:
242195 Windows 2000 Terminal Services Does Not Support Outlook Offline Storage

WARNING: The .ost file is not a backup of information on your Exchange Server mailbox. The .ost file is simply a replica of the data.
For additional information, click the article number below to view the article in the Microsoft Knowledge Base:
163589 XCLN: Restoring from an OST after Deleting the Mailbox

Article ID: 286038 - Last Review: Jul 27, 2006 - Revision: 1