Forum Discussion
Error install Cumulative Update for .NET on Server 24H2 (0x80070bc9)
Hello everyone,
I became the problem first during the .NET updates in 08/2026 and it persists until now.
During the installation of KB5127690 came an error 0x80070bc9. What I have tried:
- run the WSUS troubleshooter
- check EFI partition space (200MB / 100% free)
- rename the update cache folders
- run DISM and SFC
- check pending reboot registry keys
Unfortunately I did not find solution how to solve this problem.
There is link to CBS.log from the server (Windows Server 24H2 (26100.33650), VM on Hyper-V).
Many thanks for an answer in advance.
R.
1 Reply
Your Server 24H2 VM has repeatedly failed .NET servicing despite cache resets, DISM, SFC, and pending-reboot checks. Error 0x80070BC9 means the operation requires a reboot to roll back changes; it does not identify a particular defective update by itself. Microsoft documents a persistent case involving pending servicing and corrupted transactional entries. Compare your CBS log around the failed installation with that documented signature, particularly failures to obtain transaction state. Since you already performed the basic repairs, repeating cache resets is unlikely to provide useful evidence. Record the DISM/SFC outcomes and the relevant CBS sequence, then involve Microsoft support if the signature is unclear. For the documented transactional-corruption scenario, Microsoft recommends an in-place upgrade. Plan that repair only after a verified, application-consistent backup and compatibility review. Do not delete servicing registry entries or pending files based solely on the error code.
