Going down the IT rabbit hole

With the latest update to Configuration Manager (CM) current branch (version 2509) we’ve finally received new baseline version we can use for new site deployments. Previous baseline version is 2403 and was supported until 22nd of October, 2025. If we had any new site deployments in the last month or two, we had to go first through the deployment of an unsupported product and later on update it to the supported version (2409 and/or 2503). Since CM evaluation links are not yet updated with new baseline version, we still have to do this type of double deployment for evaluation deployments (if we want to use up-to-date systems). The same applies as well to the Windows 11 and Microsoft 365 Deployment Lab Kit download – it was updated in November 2025 with Windows 11 25H2 images, but the Configuration Manager current branch version preinstalled is as of this writing still at version 2403.

Version 2509 is currently available as an in-console update to those that are already running Configuration Manager current branch in their environment. If not, we can find baseline media on the Volume License Service Center or on Microsoft Visual Studio Download center.

General enhancements in version 2509:

• version 2509 of Configuration Manager focuses on security and quality updates (KB35877153)
• Windows 11 25H2 support
• Boot images can be automatically updated to use latest Windows Boot Loader (signed with Windows UEFI CA 2023) – only works on WDS-Less PXE-enabled Distribution Points
• Service Connection Tool improvements (better logging and error handling)
• minimum SQL 2016 or later version
• more info available at: What’s new in version 2509

More information about Configuration Manager versions, support end dates, baselines, hotfixes and more, we can find at Updates and servicing for Configuration Manager.