OL2000: (CW) Purpose and Capacity of Outlook Storage Facilities

ID: Q208480

The information in this article applies to:
  • Microsoft Outlook 2000

NOTE: These procedures only apply if you have installed Outlook with the Corporate or Workgroup option. This option allows you to use Messaging Application Programming Interface (MAPI) services. To determine your installation type, on the Help Menu click About Microsoft Outlook. In About Microsoft Outlook you should see "Corporate or Workgroup" if you have the Corporate or Workgroup installation.

SUMMARY

This article discusses the purpose and capacity of each of the following storage facilities used by Outlook when running as a client to a Microsoft Exchange Server:


MORE INFORMATION

Personal Folders Files Located on Your Computer

One or more .pst files can reside on each user's computer. A .pst can be defined as your primary store or as a secondary store. A primary store means that your mail is delivered to the Inbox in that file and all of your other default Outlook folders, such as Calendar, Contacts, Deleted Items, Journal, Notes, Sent Items, and Tasks reside there. A .pst file can be also be defined as a secondary store, meaning you can move items to it, either manually or with Inbox Rules, from your primary store.

Each .pst file can contain 16,384 folders and each folder can contain a maximum of 16,384 subfolders. If you select the option to "Allow upgrade to large tables," each folder can contain up to 65,536 subfolders. The total file size of a .pst cannot exceed 2 Gigabytes (GB).

Offline Store Files Located on Your Computer

You can synchronize the .ost and your primary store so that they always contain the same information. This allows you to work offline when the server is unavailable. When you reconnect to the server, changes made offline will be uploaded to the server and mail received while offline will be downloaded to the .ost. Only one .ost file can be used at a time.

The .ost file can contain as many root folders as you desire and each folder can contain a maximum of 16 KB subfolders. If you select the option to "Allow upgrade to large tables," each folder can contain up to 64 KB subfolders. The total file size of an .ost cannot exceed 2 GB.

Mailbox Folders Located on the Exchange Server

A mailbox folder for each user is stored on the server in the same database store. The server has a capacity that varies depending on the version and edition of Exchange Server:
  • Version 4.x and 5.0: 16GB for each server's store.


  • Version 5.5, Standard Edition: 16GB for each server's store.


  • Version 5.5, Enterprise Edition: Store sizes are restricted to drive space installed and available on the server. If larger capacity drives are installed on the server, the stores can grow to the size available.


NOTE: The server administrator may limit the size of each user's mailbox folder.

Public Folders Located on the Exchange Server

Public folders reside on the server in the same database store. They contain information shared by many users. Depending upon access permissions, individual users can create, read, update, or add to the public folder. The server has a capacity that varies depending on the version and edition of Exchange Server:
  • Version 4.x and 5.0: 16GB for each server's store.


  • Version 5.5, Standard Edition: 16GB for each server's store.


  • Version 5.5, Enterprise Edition: Store sizes are restricted to drive space installed and available on the server. If larger capacity drives are installed on the server, the stores can grow to the size available.



REFERENCES

For more information about this subject, please see the following articles in the Microsoft Knowledge Base:

Q195435 OL2000: (CW) What Are Offline Folders and How Do You Use Them?
Q156077 XADM: How to Specify Where New Public Folders Are Stored
Q149217 XCLN: Microsoft Exchange Message Size Limitations
Q143376 XADM: Storage Capacity Limits of Microsoft Exchange Server

Additional query words: OL2K

Keywords : kbdta
Version : WINDOWS:2000
Platform : WINDOWS
Issue type : kbinfo


Last Reviewed: May 13, 1999
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