Transfer is not working
A flow does not transfer any data. Follow these steps in order—each one rules out a possible cause, and the first two are the most common causes.
1. Has the change been published?
Changes to flows, plug-ins, and options do not take effect immediately. Until they are published, the runtime continues to operate using the last published version—so a newly created or modified flow is not yet recognized by the runtime.
Open “Publish” in the top navigation bar. If the flow appears there as a pending change, check the box next to it and click “Make changes productive”—see Publish.
2. Is the flow active?
A deactivated flow remains fully intact but is not executed at runtime. Right-click the flow in the snap-in bar under “Flows”: If the toggle in the context menu says “Flow deaktivieren”,” the flow is active; if the option to activate it appears there, it is not active. See Activate/Deactivate Flow .
Toggling the flow itself constitutes a change to the engineering configuration and takes effect only after Step 1.
3. What does the status tree show?
Open the Status pane. The flow node and the nodes of the involved plug-ins each have a colored dot indicating their most recently reported status—see “” under “Colors in the Status Tree” at for a list of which colors correspond to which statuses.
- A red dot on a plug-in indicates an issue with the plug-in itself, the trigger, or a missing license. Check the plug-in first, not the flow.
- If a plug-in has no dot at all, it has not yet been initialized.
- A gray dot indicates, among other things, that transfers have been shut down, stopped, or are waiting in the queue.
In the flow status, the status chart shows whether any transfers have taken place at all. Red transfer dots indicate failed transfers; if you hover over the faulty transfer object in the flow, the OPC Router will display the details.
4. Is the trigger firing?
In addition to the ready state—for example, “Ready”—the status tree shows in real time whether the flow is currently running: In Progress on the animated icon, In Queue on the queue icon. If neither is displayed, no trigger has been fired.
- A trigger error is displayed on the trigger itself and takes precedence over the activity indicator.
- If multiple triggers are linked with AND, the flow will not run until all of them have been triggered. In the flow diagram of the status view, you can see for each trigger whether it has already fired and is waiting for the others. See Flow Status .
To rule out the trigger as the cause, trigger the flow manually: In the status tree, right-click the flow and select “Trigger Flow”.” The flow does not require a trigger for this—see Triggering a Flow Manually. If it runs through successfully, the cause lies with the trigger; if it fails even then, proceed to step 5.
5. Is the target system reachable?
Most plug-ins check their connections automatically. Open the configuration for the affected connection and run the test—for database, MQTT, OPC UA, and SAP® connections, the button is labeled “Check connection”; for the mail server connection, it is labeled “Test”.” The OPC Classic connection works if you can browse the OPC servers in Management.
The configuration and the service may run in different user contexts and therefore behave differently: A successful test in Management does not necessarily prove that the runtime can establish the same connection.
For individual target systems, the troubleshooting guide lists the verification steps on a separate page:
If “” Store and Forward is enabled for the flow, the buffer itself is an indicator: If the root node Store and Forward in the status tree fills up with pending entries, the transfers are running, but the target system is not accepting them. See Store and Forward is a separate node .
6. What is recorded in the event log and the log files?
If the information on the transfer object is insufficient, check the logged messages. The event log for the dashboards and the runtime and Web Management log files contain various types of information—for details on where to find specific information and how to expand the logs for troubleshooting, see “: Log Files and Event Log” at .
7. When Support Takes Over
If none of the steps above help, create a diagnostic report at : It bundles engineering files, database backups, and log files into a single archive that you can share.