JVM startup failure after a Qlik Compose multi-hop upgrade

shashi_holla — Tue, 31 Mar 2026 13:38:27 GMT

Upgrading Qlik Compose across multiple versions requires a specific upgrade path. See Qlik Compose December 2024 Initial Release Notes for details.

After an upgrade, following the steps from 2022.5 to 2023.11 and finally 2024.12, Qlik Compose returns a generic UI error during connection tests.

UI ERROR
Unable to connect to the remote server

Reviewing the Qlik Compose server log reveals the Java process is failing to start entirely:

[INFO ] Java Server: .
[ERROR] Java Server: Error: Could not create the Java Virtual Machine.
[ERROR] Java Server: Error: A fatal exception has occurred. Program will exit.
[INFO ] Java Server: <JAVA_HOME>/lib/ext exists, extensions mechanism no longer supported; Use -classpath instead.
[WARN ] The Compose java server was restarted.
[ERROR] Java Server: Error: Could not create the Java Virtual Machine.
[ERROR] Java Server: Error: A fatal exception has occurred. Program will exit.

While the Qlik Compose server is running, the Java agent is down.

The details upgrade path followed was:

2022.5.0.2333 to 2023.11.0.1029, which was successful
2023.11.0.1029 to 2024.12.0.402, which was unsuccessful

Resolution

Stop the Qlik Compose services
Rename or remove the /ext folder in the Compose/java/lib/jre/lib directory
Start the Qlik Compose services

Cause

When the second hop was done, the installation recreated the /ext folder within Compose/java/lib/jre/lib with no files within. As Compose 2024.12 uses Java 17, it doesn’t support ext folder.

Environment

Qlik Compose

article JVM startup failure after a Qlik Compose multi-hop upgrade in Official Support Articles

JVM startup failure after a Qlik Compose multi-hop upgrade

Resolution

Cause

Environment