CBT doesn't work after KB5074109 and KB5067467 installed

[Zek]

CBT is not working anymore after 2026-01 Security Update (KB5074109) (26100.7623) and Phi Silica AI Component Update (KB5067467) installed on Win11 24H2 few days ago. Has anyone else encountered a similar problem?
Logs saying failed to read file in indexer because incorrect parameter, while vss snapshot created successfully.

Code: Select all

[18.01.2026 00:08:08] <01> Warning  Failed to generate volume (C:) CTK: Failed to calculate digests for volume \\?\GLOBALROOT\Device\HarddiskVolumeShadowCopy10
[18.01.2026 00:08:08] <01> Warning  Cannot read file in indexer::CFileWriteCollectorReadCache::_ReadBlock. Pos=0x000001d163150000 Length=0x00010000.
[18.01.2026 00:08:08] <01> Warning  Win32 error:The parameter is incorrect.
[18.01.2026 00:08:08] <01> Warning   Code: 87
[18.01.2026 00:08:08] <01> Error    Failed to create digest files
[18.01.2026 00:08:08] <01> Error    Failed to calculate digests for volume \\?\GLOBALROOT\Device\HarddiskVolumeShadowCopy10
[18.01.2026 00:08:08] <01> Error    Cannot read file in indexer::CFileWriteCollectorReadCache::_ReadBlock. Pos=0x000001d163150000 Length=0x00010000.
[18.01.2026 00:08:08] <01> Error    Win32 error:The parameter is incorrect.
[18.01.2026 00:08:08] <01> Error     Code: 87 (System.ArgumentException)
[18.01.2026 00:08:08] <01> Error       at VeeamEndpointSysUtilsDllLib.IVeeamEpSysUtils.MakeVolumeDigests(String wSnapshotName, String wNewMftDigestsFileName, Boolean vbDeviceHasSeekPenalty)
[18.01.2026 00:08:08] <01> Error       at Veeam.EndPoint.CEpMftCtpCreator.TryCreateCtpForVolume(String diskUniqueId, CLiveVolumeInfo volume, CGuestDiskInfo disk, String shadowVolumePath, EVolumeBackupMode volumeBackupMode)

Support case 07955136

[Dima P.]

Hello Zek,

Thank you for your post, this issue is unexpected. Please keep working with support team.

[Zek]

Yes, of course. However, I’d like to see feedback from other users to determine whether this issue also affects others on the same version of Windows, or if it’s an isolated case caused by a specific environment.
The issue may go unnoticed by most users, as it does not trigger any warnings or errors in the interface, but it can cause a noticeable performance degradation during backup operations on large disks.