Differences Between Exchange Server 2003 and Exchange 2000 Server
The following Microsoft® Exchange 2000 Server application development-related technologies and features were changed in Exchange Server 2003. Some technologies were enhanced, while others were removed, or are not supported in specific scenarios.
Exchange WMI Provider Changes
The Exchange Server 2003 includes new Microsoft Windows® Management Instrumentation (WMI) classes for managing Exchange Server 2003. You can read about the changes in the WMI Changes for Exchange Server 2003 section.
Active Directory Schema Changes
During installation, Exchange Server 2003 changes some class and attribute definitions in Microsoft Active Directory®. For information about the schema changes that Exchange Server 2003 makes, read the Active Directory Schema section.
Managed Wrappers for SMTP Server Event Sinks
Published in June, 2003, the technical article Writing Managed Sinks for SMTP and Transport Events provides sample code and information for both Exchange 2000 Server and Exchange Server 2003.
Exchange Server 2003 includes a new property that can be used as a standard mechanism by message filtering applications. The property indicates how confident the filter is that a message is unsolicited commercial e-mail. For more information about how to create message filtering applications, see the Anti-Spam section.
CDO Component Names Did Not Change
In Exchange Server 2003 the CDOEX library is still named "CDO for Exchange 2000". Similarly, the CDO library that ships with Microsoft Windows Server 2003 is still named "CDO for Windows 2000".
Exchange 2000 Technologies not Included with Exchange 2003
The following technologies that were included in Exchange 2000 Server are not available in Exchange Server 2003.
M: Drive Mapping Removed
The mapped M: drive is not supported in Exchange Server 2003 and is not added in either the upgrade or fresh install of Exchange Server 2003. Microsoft FrontPage® Server Extensions are also not be supported in Exchange Server 2003 because the mapped M: drive is required to upload some data to Exchange. Existing applications can no longer use the mapped M: drive functionality.
FrontPage Server Extensions Removed
FrontPage Server Extensions are not supported on Exchange Server 2003 because the mapped M: drive is required to upload some data to Exchange. Existing applications can no longer use this functionality.
Exchange Instant Messaging Removed
The Exchange 2000 Server Instant Messaging Service (IM) is no longer included in the Exchange Server 2003. Microsoft recommends migrating any applications that use Exchange 2000 Server IM to other Microsoft real-time collaboration technologies.
SQL Create Index Function Removed
The Structured Query Language (SQL) Create Index function is not supported in Exchange Server 2003 and has been removed. Applications should not attempt to use the function.
Versioning Schema Properties Removed
Versioning will not be supported in Exchange Server 2003, and the following schema properties will not be available to applications:
MAPI Technology Changes
While Extended MAPI is still used and supported with Exchange Server 2003, the following parts of Exchange MAPI are not installed, and are not supported by Exchange Server 2003. These changes affect only the MAPI system that is installed by Exchange.
- Common Messaging Calls (CMC)
- Simple MAPI
Client applications build using Simple MAPI or CMC will continue to function and be supported, provided the necessary libraries are installed on the computer where the application is running. Extended MAPI and Collaboration Data Objects (CDO) version 1.2.1 are supported with Exchange Server 2003
Visual Studio .NET Technology Support Policy
Not all Exchange technologies are supported for use in managed code applications. The Microsoft Knowledge Base article 813349 provides information about which Exchange development APIs are supported in applications using Microsoft Visual Studio® .NET and the Microsoft .NET Framework.
Anonymous Access to IIS Metabase Disabled
When you send a message using cdoSendUsingPickup without specifying a pickup directory, CDO for Exchange 2000 Server (CDOEX) searches the Microsoft Internet Information Services (IIS) metabase and determines the pickup directory for the first active SMTP service instance. However, because anonymous access to the IIS metabase has been disabled, you need to either specify which SMTP service pickup directory you want CDOEX to use by setting the smtpserverpickupdirectory Field, or ensure that your application runs under an account that has read access to the IIS metabase. Note that if you set the pickup directory in your application explicitly, subsequently changing the location of the pickup directory may cause your application to fail.
Public Folders Mail-Disabled by Default
By default, all folders under PUBLIC/NON_IPM_SUBTREE are mail-disabled. You can, however, mail enable any of these folders as necessary. Please see the Exchange SDK for instructions about how to mail enable a public folder.
savesentitems Field is ignored
The savesentitems Field has no effect when you send messages using CDOEX. A copy of the message is saved to the Sent Items folder regardless of the parameter setting. This is because the Exchange OLE DB (ExOLEDB) provider provider is hard-coded to save a copy of all sent messages to the Sent Items folder.
Exchange 5.5 Event Agent Disabled by Default
The Exchange Server 5.5 event agent continues to be shipped with, and supported on Exchange Server 2003. However, by default the agent is disabled during installation.
MSDAIPP Cannot be Run on the Exchange Server
The Microsoft OLE DB Provider for Internet Publishing (MSDAIPP) is not supported on the Exchange computer. Running MSDAIPP is supported on a computer where Exchange is not installed.