Where to find the official documentations related to schema version upgrade from 2012 R2 to 2022 AD

Hello,

You can find the official Microsoft documentation regarding Active Directory schema versions and schema update behavior in the Microsoft Learn articles below.

For the schema version mapping and upgrade details, please refer to: Active Directory Schema Versions and Updates This article documents the schema versions used by different Windows Server releases, including Windows Server 2012 R2 (schema version 69) and Windows Server 2022 (schema version 88).

For checking and validating the schema version after the upgrade, Microsoft also provides this reference: Find the Current Active Directory Schema Version

Regarding backward compatibility, Microsoft does not always state the exact phrase “schema upgrades are backward compatible” in a single sentence. However, the behavior is documented throughout the AD DS upgrade guidance and interoperability documentation. Active Directory schema upgrades are additive by design, meaning Microsoft introduces new classes and attributes while maintaining support for existing objects and applications. This is why older applications generally continue functioning after a schema extension unless they depend on deprecated behavior. ([Microsoft Learn](https://learn.microsoft.com/en-us/windows-server/identity/ad-ds/deploy/upgrade-domain-controllers-to-windows-server-2012-r2-and-windows-server-2012?utm_source=chatgpt.com"Upgrade Domain Controllers to Windows Server 2012 R2 ..."))

For the detailed lists of schema classes and attributes added or extended, the best Microsoft reference is the Open Specifications documentation here: Active Directory Schema Classes (MS-ADSC) This documentation contains the schema class definitions, object details, and related attributes used in Active Directory.

In addition, when you install a newer Windows Server version and run adprep, the actual schema changes are applied through the LDF files located in the installation media under the ADPrep folder (for example, sch69.ldf through sch88.ldf depending on the version path). These files explicitly show which objects and attributes are added during the schema extension process.

As a best practice, I still recommend validating the schema upgrade in a lab environment first and reviewing application compatibility before extending the production schema, especially for environments using Exchange, third-party LDAP integrations, or legacy identity-aware applications.

I hope this helps clarify the official references you were looking for. If you find the information useful, please consider clicking “Accept Answer”. It may also help other administrators researching the same topic.

Jason