Hi Vincent,
To my knowledge you can’t “just increase” that timeout in Mendix Cloud. The ~10-minute DB transaction limit will abort long-running actions. And I wouldn't recommend it if it was possible either...
Make it work by removing the long task from the request/transaction:
Run the conversion asynchronously:
Use Task Queue (Mendix 10) or CommunityCommons executeMicroflowInBackground.
Ensure the Java action doesn’t touch Mendix objects while converting:
Read needed data (e.g., file path/bytes) up front, then convert outside any transaction.
After it finishes, open a short microflow/transaction to save the result.
For very long/CPU-heavy work, offload to an external worker/service and poll or use a callback.
On-prem you might tweak server transaction settings, but it’s not recommended. The robust fix is: async + no open transaction during the heavy Java work.