Subworkflow Ignores Binary Data After Updating to n8n v1.74.1

Below is some guidance to help troubleshoot binary data not passing to your subworkflow:

Check Your Data Flow

n8n’s Execute Workflow node sends all incoming data (both JSON and binary) to the subworkflow’s Execute Workflow Trigger node. First, verify that the parent workflow still includes the binary data on the items reaching the Execute Workflow node. In other words, confirm that the binary data is present right before the subworkflow is called. You can check this using a simple Code node or by inspecting the data at that point.

Verify Execution Mode and Environment Settings

Since binary data handling may depend on your processing mode or environment configuration, consider these points:

• Ensure you are not unintentionally pruning binary data before the subworkflow is triggered.
• If you’re handling large files, review your binary data mode (such as keeping data in memory versus filesystem mode) via the relevant environment variables, like setting N8N_DEFAULT_BINARY_DATA_MODE to filesystem if needed. (Note that filesystem mode isn’t supported with queue mode.)

Consider Recent Changes in v1.74.1

As you observed a change in behavior following the update to v1.74.1, it is possible that there was an unintended side effect or a subtle change in how binary data is serialized between workflows. This can be confirmed by looking at the community forums or GitHub issues for any similar reports specific to version 1.74.1.

Next Steps

• Double-check that the binary data is not being removed or modified unexpectedly in the parent workflow before the call to the subworkflow.
• If possible, test a simplified version of your workflow that only passes a dummy binary file to see if it makes it to the subworkflow.
• Consult the community or file an issue if the behavior seems to be a regression.

If you continue to experience problems, consider sharing a reproducible example with the community for further feedback.

Hopefully, these tips help you pinpoint and resolve the issue with binary data not being transmitted correctly to your subworkflow.