Error activating Windows Server 2019 in the latest version

[xf22cn]

After updating py kms: minimal to the latest version, use the following command to test on Win10:
.\vlmcs.exe -v -l 3 kms-server-ip
Return error message:

Request Parameters

Protocol version : 6.0
Client is a virtual machine : No
Licensing status : 2 (OOB grace)
Remaining time (0 = forever) : 43200 minutes
Application ID : 55c92734-d682-4d71-983e-d6ec3f16059f (Windows)
SKU ID (aka Activation ID) : 34e1ae55-27f8-4950-8877-7a03be5fb181 (Windows Server 2019 Datacenter)
KMS ID (aka KMS counted ID) : 8449b1fb-f0ea-497a-99ab-66ca96e9a0f5 (Windows Server 2019)
Client machine ID : 38d7cc4c-c604-4c9c-8c90-2245be50287a
Previous client machine ID : 00000000-0000-0000-0000-000000000000
Client request timestamp (UTC) : 2025-11-17 01:14:38
Workstation name : we-love.ubuntu.pro
N count policy (minimum clients): 5

Connecting to 172.16.18.68:1688 ... successful

Performing RPC bind ...
... NDR32 ... BTFN ... successful
Sending activation request (KMS V6)
Fatal: No RPC response received from server

Error 0x0000071C while sending request 1 of 9
Communication failed during remote procedure call.

The above is the error output information.
I checked the output log of the server and found no information about successful activation.

The version released a few days ago also had the same issue.
Earlier versions do not have this issue and can pass testing normally.

[xf22cn]

Supplement the output logs of the server:

Mon, 17 Nov 2025 12:36:47 INFO Connection accepted: ::ffff:172.16.18.114:59546
Mon, 17 Nov 2025 12:36:47 INFO RPC bind request received.
Mon, 17 Nov 2025 12:36:47 INFO RPC bind acknowledged.
Mon, 17 Nov 2025 12:36:47 INFO Received activation request.
Mon, 17 Nov 2025 12:36:47 INFO Received V6 request on Mon Nov 17 12:36:47 2025.
Mon, 17 Nov 2025 12:36:47 WARNING Module 'tzlocal' or 'pytz' not available ! Request time not localized.
Mon, 17 Nov 2025 12:36:47 WARNING Too many clients ! Fixed with 10
Mon, 17 Nov 2025 12:36:47 INFO Machine Name: ns1.google.at
Mon, 17 Nov 2025 12:36:47 INFO Client Machine ID: d94a8218-858a-4a31-a756-9d99f4e9d606
Mon, 17 Nov 2025 12:36:47 INFO Application ID: Windows
Mon, 17 Nov 2025 12:36:47 INFO SKU ID: Windows Server 2019 Datacenter
Mon, 17 Nov 2025 12:36:47 INFO License Status: Grace Period
Mon, 17 Nov 2025 12:36:47 INFO Request Time: 2025-11-17 04:36:47 (UTC)
Mon, 17 Nov 2025 12:36:47 INFO Connection closed: ::ffff:172.16.18.114:59546

[xf22cn]

I checked the information and found that the activation requirement for the server is that the number of client activations must be at least 25. May I ask if this issue is caused by insufficient activation settings on the client side? I saw one sentence in the log:

Mon, 17 Nov 2025 12:36:47 WARNING Too many clients ! Fixed with 10

In previous versions, this value was set to 25
If that's the reason, I hope it can be corrected as soon as possible.
I can't thank you enough.

[didotb]

is the error really starting with 0x0? All activation error codes start with 0xC and 0x8, your error code indicates a driver problem somehow.

[didotb]

I'm able to activate my newly installed Server 2019 Datacenter Core, sometimes you might need to retry multiple times if you see a 0xC in the error code.
But as I mentioned previously, the error code given to you suggests a driver error on your Windows Server 2019.

[xf22cn]

I used the program "vlmcs-Windows-x64.exe" on a Windows 10 system for testing.

The test was performed in the command prompt (cmd).

The command used was:

.\vlmcs.exe -v -l 3 kms-server-ip

This test passed easily in earlier versions without errors.

However, it failed in the newer version. I tested it more than 10 times, and it never returned a successful activation message.

Please refer to my previous information for error messages and server log output.

[xf22cn]

I might need to install a Windows Server 2019 virtual machine for testing?

I'll start this test later, but I'm not sure I can report the results quickly.

I've been a bit busy these past few days…

[xf22cn]

I used a different testing method.

I installed another docker-kms service program on the same Debian host. The link is as follows:

https://github.com/11notes/docker-kms

The test passed.

I think this is indeed an issue that might need to be fixed.

[xf22cn]

Today I installed Windows Server 2019 Standard Edition in a virtual machine for testing, but unfortunately, activation failed.

A screenshot of the error message is as follows:

The server logs are as follows:

Mon, 17 Nov 2025 22:14:09 INFO Connection accepted: ::ffff:172.16.18.107:49698
Mon, 17 Nov 2025 22:14:09 INFO RPC bind request received.
Mon, 17 Nov 2025 22:14:09 INFO RPC bind acknowledged.
Mon, 17 Nov 2025 22:14:09 INFO Received activation request.
Mon, 17 Nov 2025 22:14:09 INFO Received V6 request on Mon Nov 17 22:14:09 2025.
Mon, 17 Nov 2025 22:14:09 WARNING Module 'tzlocal' or 'pytz' not available ! Request time not localized.
Mon, 17 Nov 2025 22:14:09 WARNING Too many clients ! Fixed with 10
Mon, 17 Nov 2025 22:14:09 INFO Machine Name: WIN-7KCV3TA5B39
Mon, 17 Nov 2025 22:14:09 INFO Client Machine ID: 4098274c-1047-4548-bfa1-c73d9855ba2c
Mon, 17 Nov 2025 22:14:09 INFO Application ID: Windows
Mon, 17 Nov 2025 22:14:09 INFO SKU ID: Windows Server 2019 Standard
Mon, 17 Nov 2025 22:14:09 INFO License Status: Notifications Mode
Mon, 17 Nov 2025 22:14:09 INFO Request Time: 2025-11-18 03:14:07 (UTC)
Mon, 17 Nov 2025 22:14:09 INFO Connection closed: ::ffff:172.16.18.107:49698

[xf22cn]

To add, I tried to activate it multiple times afterward by running the activation command, but it still failed.

[xf22cn]

The error message in the screenshot is:

Error: 0xC004F074 The software license server reports that it cannot activate the computer and cannot contact any key management service (KMS).For further information, please refer to the application event log.

[didotb]

that's odd, I retested mine as well using minimal, I still was able to activate the same server 2019 datacenter.
What's your environment variables on the py-kms?

WARNING Too many clients ! Fixed with 10

I also see the same thing on my logs, but activation still isn't a problem.

[didotb]

I just checked with an older image, and the warning message WARNING Too many clients ! Fixed with 10 exists only for Windows Server editions, never on consumer editions.

[xf22cn]

When I created the Docker container, I used the command provided by the official documentation:

sudo docker run -d --name py-kms --restart always -p 1688:1688 -v /etc/localtime:/etc/localtime:ro pykmsorg/py-kms:latest

The host machine is a Debian 12 system specifically installed for KMS services. A clean install was used, and the system was updated to the latest version after installation. The only software installed is SSH and dcoker.

[didotb]

I have finally gotten the time to work on my PVE.

Can confirm; somehow crashes before ePID calculation on alpine, and debian 12 and 13; using latest / minimal, python3, and python3-next tags

I have forgotten I also have a redundant server that is currently running an older image, which is probably what was replying to the Server 2019's request.

Below is the py-kms' reply after turning on debug log level

[xf22cn]

Today I took some time to set up a CentOS Stream 9 virtual machine and then built a py-kms server on it.

The server was minimally installed, with only SSH and Docker installed.

Unfortunately, the test still failed.

This time, I used a Windows Server 2019 virtual machine installed on a different physical host.

The error logs were identical to those I provided earlier.