Error overview
When deploying Flows containing the Send Email Action, customers may encounter validation errors such as:
"The value in ‘<actionName>’ is either missing or contains multiple fields. Enter a single value."
Salesforce’s Simple Email Action (v2.0.1) introduced new required data structures for:
recipientAddresses
ccAddresses
bccAddresses
These parameters are only supported starting with API v65.
When a tool retrieves Flow metadata using API v64 or below, Salesforce does not return values for these inputs. As a result, the Flow's XML contains empty <value/> tags for these address parameters:
<inputParameters>
<name>recipientAddresses</name>
<value /> <--- Empty
</inputParameters>
<inputParameters>
<name>ccAddresses</name>
<value /> <--- Empty
</inputParameters>
<inputParameters>
<name>bccAddresses</name>
<value /> <--- Empty
</inputParameters>
When retrieved using API v65, Salesforce returns the proper data structure:
<inputParameters>
<name>recipientAddresses</name>
<value>
<collectionElements>
<stringValue>test.email@gearset.com</stringValue>
</collectionElements>
</value>
</inputParameters>
Resolution
Since Gearset lets you control the API version of a comparison, navigate into your Metadata filter and select Winter '26 (65):
For pipelines: Make sure every environment in the pipeline is set to use API v65. If you’ve already pushed a commit created with API v64 (or lower), those address fields will be stored as empty in the commit. In that case, update the API version to v65 in your initial dev environment, re-retrieve the Flow to generate a fresh commit, and promote that new commit through the pipeline.
See our How do I change the API version that Gearset uses? article for step-by-step instructions on changing the API version in Compare and deploy, for your Pipeline or in CI jobs.
What if I can't update the API version?
If your org still relies on an older API version, you’ll need to remove the Send Email (v2.0.1) action from the Flow.
Disclaimer: This error is returned by Salesforce directly, rather than Gearset. Even so, we offer guidance based on our combined experience with the Metadata API. Where possible, we try to help guide you to fix or avoid this error. In the case that this isn't possible, we may need to direct you to Salesforce support for further clarification.