Step Error Messages
Use the exact text from the step’s Executions tab to find the matching remedy. These messages identify configuration or input that the Step cannot accept.
“Combine needs exactly two incoming branches”
Symptom: A Combine step fails before it does any work. The message names branches rather than lists.
The Cause: Combine takes one list from each of two connected branches. One branch, or three, and it cannot tell which is which.
The Fix: Count the lines arriving at the step. Add the missing branch, or take the extra one out.
Related: “Combine must wait for both incoming branches. Set its branch wait mode to AND.” Combine always waits for both of its inputs, so its wait mode is fixed and the chip on it is a label rather than a control. If you see this message, delete the Combine step and add it again to restore its wait mode.
“First list and Second list must refer to different connected branches”
Symptom: Combine refuses, and both list fields look correctly filled in.
The Cause: Both fields point at the same branch. Combining a list with itself has no useful answer.
The Fix: Open Second list and pick from the other branch.
“Sort needs at least one ‘Sort by’ row”
Symptom: Sort fails immediately.
The Cause: No rule has been added, so there is nothing to order by.
The Fix: Add a Sort by row: a field, a type and a direction. Leave the field blank to compare each whole item, which is what you want for a list of plain values.
Related: “Limit needs a number of items to keep” and “Limit’s ‘Number of items’ must be a whole number of zero or more” mean the count is missing or is not a whole number. Zero is allowed and returns an empty list.
“The list was empty, so this loop ran no passes”
Symptom: A Repeater finished at once. Nothing inside the loop ran, and the step is not marked failed.
The Cause: The list it was given had no entries. That is not an error, and the run carries on from When finished.
The Fix: Nothing, if an empty list is possible in normal use. If it should never be empty, look at the step that produced it: a Filter that discarded everything, or a fetch that returned nothing, are the usual reasons.
“The loop finished but nothing connected back into it”
Symptom: A Repeater ran, but no results came out of it.
The Cause: A loop turns because the last step of its body connects back into the Repeater. Without that returning line, each pass runs and its output goes nowhere.
The Fix: Draw a connection from the last step inside the loop back to the Repeater step.
“can work on at most 100,000 items at once”
Symptom: Sort, Limit or Remove duplicates refuses, naming both the ceiling and your list’s length.
The Cause: These steps hold the whole list in memory to work on it, and 100,000 entries is the ceiling.
The Fix: Reduce the list before it reaches the step. A Filter that removes what you do not need, or fetching in pages, are both cheaper than trying to process everything at once.
“approverEmail is required but was not provided”
Symptom: A Human Review step fails instead of waiting for somebody.
The Cause: No approver address, or one that is not a single valid email. A list of addresses is not accepted here.
The Fix: Set one address. If it comes from an earlier step, check what that step actually produced: a field holding several addresses, or an empty one, fails the same way.
What’s Next?
- Find the failing step and its input with Debug a Run.
- Check list and field references in Data and Mapping Problems.
- Review platform-wide ceilings in System Limits & Quotas.