We recently upgraded our Windows Server from 2019 to 2025 and now I can no longer run Windows containers in process isolation, even when the docker image’s kernel matches the host. Interestingly enough, it does work with running in 2022 based images though.
I’m running Microsoft Windows [Version 10.0.26100.1742]
docker run -ti --isolation=process python:windowsservercore-ltsc2022
This Works!
docker run -ti --isolation=hyperv python:windowsservercore-ltsc2022
This Works!
docker run -ti --isolation=hyperv python:windowsservercore-ltsc2025
This Works!
docker run -ti --isolation=process python:windowsservercore-ltsc2025
docker: Error response from daemon: container 52b6e2af7f149add170e1f37322e442576bfa9687d31687222b9dab025dea366 encountered an error during hcs::System::Start: failure in a Windows system call: The virtual machine or container exited unexpectedly. (0xc0370106)
Using the shared tag for the latest python image also produces the error.
docker run -ti --isolation=process python
docker: Error response from daemon: container 52b6e2af7f149add170e1f37322e442576bfa9687d31687222b9dab025dea366 encountered an error during hcs::System::Start: failure in a Windows system call: The virtual machine or container exited unexpectedly. (0xc0370106)
I didn’t even know there was a Windows Server 2025, so I haven’t heard about related issues yet. Have you tried asking about it from the Microsoft community? Even though the docker command is used, as far as I know, process isolation depends on Windows entirely and I don’t see many advanced Windows server users around here.
Sorry for the delay, let me run some tests here and come back to this thread.
Can you please share more on how you got Docker installed on Windows Server 2025?
So, @henryborchers you need update the Windows Server OS.
The explanation here is that the Windows Server 2025 Server Core base image that Python uses has been updated (and there’s an ABI incompatibility to older host OS versions). The build you are using is from 23H2 (which coincidently is the same as the current evaluation media for Windows Server, so I was able to reproduce exactly the same error as you found). By updating the host, you should be able to run the image with process isolation.
@vrapolinario you were right!! It looks like the machines that were updated to Windows Server were fixed on the RTM version. After fixing this and updating the kernel, it worked!
Thank you it also helped me to run a Windows Server Core 2025 container on a Windows Server 2025 host with build 26100.3781.
However, as stated in the official documentation (Windows container version compatibility | Microsoft Learn), a container using process isolation should run without issues as long as the host and container OS have the same build version. In this case, both the host (26100.1742) and the container (26100.3781) share the same build number (26100), so it should work.
That said I thing it might be worth noting this in the documentation to help others.