How the Exchange 2003 Active Directory Connector Setup Process Updates the Schema

This article describes how the Exchange 2003 Active Directory Connector (ADC) Setup process updates the schema.

In Exchange 2003, the schema files that are imported when you install or upgrade the ADC are the same as the core Exchange 2003 schema; therefore, updates to the schema occur only one time. The ADC Setup process detects the schema version to determine the existence of the Exchange 2003 schema. If the schema version is earlier than 6870, the Setup process applies the Exchange 2003 schema updates. If the schema version is later than 6870, the Setup process detects the existence of the Exchange 2003 schema and the Setup process does not apply additional schema updates.

Note Although Exchange 2003 ADC Setup installs all the Exchange Server 2003 schema updates, it does not import Microsoft Outlook templates or the new security settings. Therefore, you still have to use the setup /forestprep switch. However, if you have a large organization, you do not have to worry about administrative lockdowns while you wait for additional schema changes to replicate because the schema extensions are skipped.

When you run the ADC Setup program, Setup examines the rangeUpper attribute of the following object in Active Directory to detect the schema version: If a domain controller does not show a value of 6870 for the rangeUpper attribute, the schema extension has not yet completed. Setup examines the rangeUpper attribute because there are no more schema updates beyond rangeUpper. The rangeUpper attribute is the last entry that is added to the Schema9.ldf file (this file is located in the Adc\I386 folder on the Exchange 2003 CD-ROM). The following data is an example of the file entry for the rangeUpper attribute:Unlike Exchange 2003, the ADC schema files in Exchange 2000 are a subset of the Exchange 2000 core schema files. When you use the Exchange 2000 ADC setup /schemaonly switch, the schema is extended. However, you must also run the setup /forestprep switch to install additional schema extensions. As a result, there are longer lockdown periods for larger organizations whose custom programs are sensitive to schema extensions. The delay occurs because replications are delayed and because partial attribute sets must be reset.

For additional information about schema partial attribute sets, click the following article number to view the article in the Microsoft Knowledge Base: