In the past developing anything for Exchange 2000/2003 required an array of knowledge since you had to do each task a different way, whether it was leveraging CDOEx or WMI or ADSI it was complicated. There are a lot of changes in Exchange 2007 for the better other than having to learn one more way to do things. Do you have plans to leverage this new interfaces for your design?
Here is a list of changes in 2007
Routing groups
Exchange 2007 uses Active Directory site-based routing. Routing groups are no longer needed.
Administrative groups
Exchange 2007 uses the Exchange 2007 split permissions model that is based on Universal Security Groups (USGs).
Intelligent Message Filter
Exchange 2007 uses anti-spam agents in the Hub Transport and Edge Transport server roles.
Link state routing
Exchange 2007 uses Active Directory site-based routing. Link state routing is not used.
Routing objects
Exchange 2007 uses Active Directory site-based routing. Routing objects are no longer used.
Network-attached storage
Exchange 2007 supports Internet SCSI (iSCSI).
Exchange Installable File System (ExIFS)
Exchange Web Services or MAPI enable you to perform the necessary tasks.
Event service
Retain a computer that is running Exchange 2000 or Exchange 2003 in the Exchange 2007 organization if you need this functionality.
Exchange extensions in Active Directory Users and Computers
Recipient management is included in the Exchange Management Console in Exchange 2007.
Microsoft Exchange Server Mailbox Merge Wizard (ExMerge.exe)
The Exchange Management Shell Export-Mailbox cmdlet or the Move Mailbox Wizard can be used to perform the necessary mailbox tasks.
Recipient Update Service (RUS)
Use the Update-AddressList and Update-EmailAddressPolicy Exchange Management Shell cmdlets. To replace the full functionality of RUS, you can schedule these Exchange Management Shell commands by using the Task Scheduler in Microsoft Windows Server 2003.
Installing Exchange Server 5.5 into an Exchange 2007 organization
Move the mailboxes from Exchange Server 5.5 to Exchange 2000 or Exchange 2003, and then move them to your Exchange 2007 servers by using Exchange Management Shell cmdlets or the Move Mailbox Wizard.
Support for Exchange Server 5.5 in the same forest as Exchange 2007
Installing Exchange 2007 into an organization that contains computers that are running Exchange Server 5.5
Move the mailboxes from Exchange Server 5.5 to Exchange 2000 or Exchange 2003. Install Exchange 2007, and then move the mailboxes to your Exchange 2007 servers by using Exchange Management Shell cmdlets or the Move Mailbox Wizard.
Active Directory Connector (ADC)
Exchange 2007 does not directly interoperate with Exchange Server 5.5.
Site Replication Service (SRS)
Outlook Mobile Access
Switch to Exchange ActiveSync.
Outlook Mobile Access Browse
Use a hardware device that supports Exchange ActiveSync.
Exchange ActiveSync: SMS Always-Up-To-Date
Switch to Direct Push technology.
Exchange ActiveSync: S/MIME abilities
S/MIME control
Retain a computer that is running Exchange 2000 or Exchange 2003 in the Exchange 2007 organization if you need this functionality
Rules, post forms, monthly calendar view
Custom forms
Editing personal distribution lists
URL commands except for free/busy, galfind, navbar, and contents
Use Exchange Web Services
Public folder access
Exchange Web forms
Use Outlook Web Access custom forms
Public folder graphical user interface (GUI) management
Non-MAPI top-level hierarchies in a public folder store
Public folder access by using Network News Transfer Protocol (NNTP)
Public folder access by using IMAP4
NNTP
POP3 or IMAP4 graphical user interface (GUI) management
Use Exchange Management Shell cmdlets.
X.400 Message Transfer Agent (MTA)
SMTP virtual server instances
Use Exchange 2007 SMTP connectors.
Microsoft Exchange Connector for Novell GroupWise and migration tools
Microsoft Exchange Connector for Lotus Notes
Use the appropriate tools for coexisting and migrating from Lotus Notes available at the Resources for Moving to the Microsoft Collaboration Platform Web site.
Active/active clustering
Switch to active/passive clustering.
Transport event hooks
Workflow Designer that was included with the Exchange 2003 SDK
Use Windows Workflow Services (WWS).
Collaboration Data Objects (CDO) for Workflow that was included with Exchange 2003.
Microsoft Collaboration Data Objects for Exchange Management (CDOEXM)
Exchange Windows Management Instrumentation (WMI) classes
MAPI client and CDO 1.2.1 on the Exchange installation
Exchange 2007 no longer depends on these components. They are a separate component that will be available for download. For more information about how to download the required components, see MAPI client and CDO 1.1.2 and CDO, version 1.2.1.
Monitoring and status node
Use a monitoring solution such as Microsoft Operations Manager.
Message Tracking Center node and tracking mechanism
Use the Exchange Server Mail Flow Analyzer.
Mailbox Recovery Center
Use the Exchange Server Disaster Recovery Analyzer.
Mailbox Management Service
Use Messaging Records Management.
Clean Mailbox tool
Use the export-mailbox Exchange Management Shell cmdlet.
Migration Wizard
Use the move-mailbox Exchange Management Shell cmdlet.
ExProfRe
Use the Autodiscover service.
Inter-Organization Replication tool
If you are using Microsoft Office Outlook 2007 to access e-mail, you can use the Availability service to share free/busy data across forests. The Availability service is supported only for Outlook 2007 clients. If you are using any other versions of Outlook, you must install an Exchange 2000 or Exchange 2003 server into the Exchange 2007 organization and use the Microsoft Exchange Inter-Organization Replication tool to synchronize free/busy data across multiple forests.
There are legacy Exchange features that are now being deemphasized in Exchange 2007:
- Joel