OL98: (CW) What Are Offline Folders and How Do You Use Them?

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When you use Microsoft Outlook 98 with the Microsoft Exchange Server Information Service, you have the ability to 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.

Offline folders are only available with Microsoft Exchange Server.

More information

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

Offline folders are stored in an offline folder file (.ost); the default location for the .OST is your current Windows folder. Like Personal Folders (PST), the .OST 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 Microsoft Exchange Server 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 Microsoft Exchange Server.

When working offline, you work with the contents of an offline folder exactly as you do with a folder 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 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 will be deleted from both after synchronization.

Creating an Offline Folder File

To create an offline folder file, follow these steps:

  1. On the Tools menu, click Services.
  2. Click to select Microsoft Exchange Server, and then click Properties.
  3. On the Advanced tab, click the Offline Folder File Settings.
  4. Type the path to the file you want to use as the offline folder file.
  5. If the message stating that the "<path><filename>..ost could not be found. Would you like to create it?" appears, click OK.
  6. Click OK and OK.
NOTE: The client must be connected to the Exchange Server for the initial creation and synchronization of the Offline Folder file.

All of the standard Outlook folders Inbox, Outbox, Deleted Items, Sent Items, Calendar, Contacts, Journal, Notes, and Tasks on the Microsoft Exchange Server are now ready for offline use. You cannot selectively choose which will be available for offline use and which will not be. To set Public Folders for offline use, see the "Working with Public Folders Offline" section in this article.

To set any user-defined folders for offline use, follow these steps:

  1. Right-click the user-defined folder and click Properties on the shortcut menu.
  2. On the Synchronization tab click to select "When offline or online" from the "This folder is available" section.
  3. Click OK.
You cannot use an .ost file that has previously been used with a different mailbox. Doing so produces the following error message:
The file <filename>.ost cannot be accessed because it has been configured for use with a different mailbox.
NOTE: When you start Windows, do not press ESCAPE when prompted for the Windows password, or you will not be able to access the .ost file because the proper credential information has not been supplied.

Working with Public Folders Offline

To work with public folders offline, follow these steps:

  1. Using the right mouse button (right-click), click the public folder that you want to work with, and click Copy "<FolderName>" on the shortcut menu.
  2. In the Copy Folder dialog box, move to your Favorites Folder, and click OK.
  3. From your Favorites Folder, right-click the newly copied folder, and click Properties on the shortcut menu.
  4. Click the Synchronization tab and click to select "When Offline or online."
  5. Click OK.
Your Public Folder is now ready for offline use. Each folder that you copy to your Favorites Folder can now be selectively set for offline use.

When you synchronize, a log file appears as a message in your Deleted Items folder. This log file contains information such as the time you synchronized, the names of the folders synchronized, and the number of items added.

To synchronize offline folders, use one of the following methods.

Synchronizing a Specific Folder

To synchronize a specific folder, click to select the folder you want to synchronize, on the Tools menu, click Synchronize and then click This Folder.

Synchronizing All Folders

On the Tools menu, click Synchronize and then click All Folders to synchronize all your offline folders.

Automatically Synchronizing All Folders When You Quit Outlook

To automatically synchronize all folders when you quit Outlook, follow these steps:

  1. On the Tools Menu, click Options and then click the Mail Services tab.
  2. In Mail Options, select the Enable Offline Access check box and then select the "When online, synchronize all folders upon exiting" check box
  3. Click OK.
All folders that are available offline will now be automatically synchronized when you quit Outlook.

It is important to synchronize and download the Address book before you log off the Microsoft Exchange Server. This is particularly important when going on the road for the first time to ensure that all your offline folders will be updated before you leave.

To download your address book, use the following steps:

  1. On the Tools menu, click Synchronize and click to select Download Address Book.
  2. Select either Download the offline address book with or without details information and click OK.
Note that the Download Offline Address Book dialog box contains information concerning the ramifications of downloading without detail information.

The Remote Mail feature is not available if you are set for Offline Folder use. For more detailed information about Remote Mail and how to use it, please see the following article in the Microsoft Knowledge Base:
ARTICLE-ID: 180418
TITLE : OL98: (CW) Remote Mail, Offline Folders, and Working Offline

Setting Which Folders Are Available Offline

You can control which folders in the exchange mailbox are available offline, and therefore, in your OST file on a folder-by-folder basis.
  1. On the View menu, click Folder List.
  2. Right-click the folder you want included in your OST synchronization, and then click Properties.
  3. Under the Synchronization tab under "This folder is available," click to select "When offline or online."
Note: When you synchronize your choices are "All Folders" or "This Folder." "All Folders" means all folders that have the available when offline or online property set. "This Folder" means the folder you have open. You cannot set to synchronize a specific group of folders on the fly.

Synchronizing Two Computers To the Same Mailbox

In order to synchronize two computers to the same mailbox, they must be synchronized individually. While multiple computers can connect to the same mailbox at the same time, only one can synchronize at a time. The synchronizations can be performed during the same session, but not simultaneously.


Article ID: 182158 - Last Review: October 26, 2013 - Revision: 2.0
Applies to
  • Microsoft Outlook 98 Standard Edition
kbnosurvey kbarchive kbinfo KB182158

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