Forum Discussion

Iron Contributor

Feb 26, 2024

26063 deduplication data corruption is still there.

From Server 2022 up to this newest 26063 build, they all have the same problem, as described here: https://techcommunity.microsoft.com/t5/windows-server-insiders/server-vnext-26040-and-server-2022-de...

Hyper-V

storage

MSBernstein

Microsoft

May 09, 2024

Hi, Joachim. MSSWRahman had asked you for a full dump and logs - were you able to hand those off? I understand that you can perfectly reproduce the issue, but we have not been able to reproduce this in-house at all.

Joachim_Otahal

Iron Contributor

May 10, 2024

The full dump and the logs are requested for a different machine, an i7-4960x running Server 2022, which did no crash again yet to have such a dump - I activated the "full dump please" option. That single crash may be completely independent from that deduplication issue, which I reproduce in machines I have more confidence in (both have ECC RAM, for example). The i7-4960x machine may show its age since it is eleven years old now, so I have to rule it out as reliable test machine for the deduplication issue.

Lupo65
Copper Contributor
Oct 30, 2025
Hello Joachim, I know, this is long ago but did you receive a satisfactory response from MS / could you solve it (I understand a possible workaround for you was to switch from NTFS to ReFS on the disk(s) in question?)? I am asking as I am experiencing the same issue on a physical W2k25 server: As soon as i enable deduplication on the disk there will be corruptions after the dedup job finished on the volume - when the VMs have been running.
(I have a different physical W2k25 as HyperV-Host with no issues - so there might be a dependency on CPU or specific hard disks)
However, my first question is how this thread here ended?