Offline key does not provide access to Flow 24.9.25 in Azure DevOps pipeline

[wen.long.sun]

Hi,

we are having problems building our Vaadin project in an Azure DevOps pipeline when using an offline license key.

Our project is configured to use Vaadin 24.9.20 and the vaadin-maven-plugin version 24.9.20. The pipeline task runs Maven like this (simplified):

bash

mvn -f pom.xml -q -B -ntp \
  -Dmaven.repo.local=... \
  "-Dvaadin.offlineKey=***" \
  "-Dlogback.configurationFile=logback-pipeline.xml" \
  "-Djava.library.path=target\natives" \
  compile vaadin:build-frontend

However, the build fails in the pipeline with the following error:

vbnet

[ERROR] The build process encountered an error: The offline key does not provide access to flow 24.9.25
[ERROR] Failed to execute goal com.vaadin:vaadin-maven-plugin:24.9.20:build-frontend (default-cli) on project [project-name]: null: MojoFailureException: InvocationTargetException: The offline key does not provide access to flow 24.9.25

What is confusing is that:

• Locally, the same project builds successfully with the same Vaadin version and offline key.
• The project is explicitly set to Vaadin 24.9.20, but during the pipeline build it seems to try to use Flow 24.9.25, which is not covered by our offline key.

We suspect this might be a bug or some mismatch between the Flow version that the plugin is trying to use and the version covered by the offline key when running in a CI environment.

Questions:

1. Why would the build-frontend goal for Vaadin 24.9.20 require access to Flow 24.9.25 in this scenario?
2. Is this a known issue with Vaadin Flow 24.9.x and offline keys in CI (Azure DevOps) environments?
3. Is there a recommended way to force the pipeline to use exactly the Flow version that matches our Vaadin version / license, or any configuration we might be missing?

Any hints or guidance would be greatly appreciated.

Thanks in advance,

Sun Wen-Long
AON (Italy)

[Tatu2 (Tatu Lund)]

That error is expected if you do not have Vaadin subscription plan, which includes commercial maintenance of the legacy versions. Check this announcement.

Vaadin 24 Free Maintenance Has Ended — Here's what you need to know

Hi everyone, As of June 16, 2026, free maintenance for Vaadin 24 has ended. We want to make sure everyone understands what this means and what your options are. What changed: Vaadin 24 will no longer receive free security patches, browser compatibility fixes, or critical bug fixes. Your applications will continue to run — nothing breaks overnight — but newly discovered vulnerabilities and browser changes will no longer be addressed on the free track. If you’re still on V24, you have two paths…

If you already have such subscription plan, you just need to download the license key. The other options are either to upgrade to the latest Vaadin 25 version, or if you have technical limitations blocking to do so, contact our sales team.

[marcoc_753 (Marco Collovati)]

I suggest to run mvn dependency:tree -Dincludes=com.vaadin:flow-server -Dverbose to check the origin of the 24.9.25 version.

[wen.long.sun]

So it’s because AON has got PRO level subscription?
Legacy support is not more supported?
I’ve understand taht 24.10.x was “out of plan”
Not the 24.9.x

Anyway, we are planning to move on 25.x
But we have several Java bugs and upgrade to do, in the dependencies.

[Leif (Leif Åstrand)]

Vaadin 24.9 was supposed to “end” at version 24.9.18 but then we introduced a new feature for the Enterprise subscription to also have access to maintenance for older minor versions. Since we have Enterprise customers that rely on Vaadin 24.9, we have subsequently released Vaadin 24.9.19 and 24.9.20 as commercially maintained versions. We should really adjust the error message specifically for these cases where it might be unexpected that a version has become commercial.

The release notes for Vaadin 24.9.20 declare that the included Flow version is 24.9.25 so there’s no mystery about why you get that version. The patch versions can in some cases get out of sync between the main Vaadin releases and individual parts such as Flow and this did for various reason happened repeatedly in the case of Vaadin 24.9 so that the delta has reached 5.

The final small mystery is why the same build works for you locally but not on the server. My guess there is that you have accidentally enabled a trial for the commercially maintained version so that’s why to doesn’t complain right now but it would probably start complaining soon.

[wen.long.sun]

Anyway
I’ve rollback to Vaadin 24.9.18
And forced Netty’s version to the LATEST

That’s a valid legit workaround for the last 24.9.x supported version by Vaadin Pro License.

Peace