How to Add Error Handling in Salesforce Flow?

Adding robust error handling in Salesforce Flow is crucial for maintaining data integrity, providing a smooth user experience, and ensuring your automations run reliably. The primary mechanism for error handling in Flow is the Fault Path, which allows you to define alternative actions when a flow element encounters an issue.

Understanding Flow Error Handling

When an element in a Salesforce Flow fails to execute successfully—perhaps due to a missing required field, insufficient permissions, a validation rule, or an external system error—it triggers a "fault." Without explicit error handling, the flow will typically halt, displaying a generic error message to the user or failing silently in the background, making troubleshooting difficult. By implementing fault paths, you can proactively catch these errors and define specific actions.

Key components for effective error handling include:

Fault Paths: Special connectors that activate when an element fails.
$Flow.FaultMessage Variable: A built-in global variable that stores the detailed error message when a fault occurs.
Logging Mechanisms: Storing error details for later review.
Notifications: Alerting administrators or relevant users about failures.
User Feedback: Providing clear, actionable messages to end-users.

Implementing Error Handling with Fault Paths

To add error handling, you connect a fault path from any element that might fail to another element designed to handle that failure.

Step-by-Step Guide to Error Handling

Here’s how to implement error handling in your Salesforce Flow:

Identify Potential Faulty Elements:
Any element that interacts with the Salesforce database (like Create Records, Update Records, Delete Records), calls an Apex action, or integrates with an external system (like External Action) can potentially fail. Focus on these elements first.
Add the Fault Path:
- In the Flow Builder, click on the element that might fail (e.g., a Create Records element).
- You'll see two connectors emerging from it: the standard successful outcome connector (usually a solid line) and a fault connector (often a red dashed line or a specific "Add Fault Path" button).
- Drag the fault connector to a new or existing element that will handle the error.
Define Fault Actions:
Once you've added a fault path, you need to decide what actions to take. Common actions include:
- Logging the Error: Creating a record in Salesforce to store details of the error.
- Notifying Users/Admins: Sending an email or displaying a screen message.
- Attempting Recovery: In some cases, you might try an alternative action.

Example: Logging Errors by Creating a Case

A robust error handling strategy often involves logging error details for administrative review. Here's how you can create a Case record to capture the fault message:

Select the Potentially Failing Element:
For instance, imagine you have a Create Records element that tries to create a custom object record.
Add a Fault Path from the Element:
Drag the fault connector from your Create Records element to a new Create Records element.
Configure the Error Logging Element:
This new Create Records element will be responsible for creating a Case to log the error.
- Label: Provide a descriptive label, such as Create Case
- API Name: Assign an API name, for example, Create_Case
- Object: Select the Case object.
- Set Field Values for the Case:
  - Field (Description): Select the Description field.
  - Value: Input {!$Flow.FaultMessage}. This will automatically populate the Case's Description field with the exact error message that caused the fault in the previous element.
  - You can also set other fields like Subject (e.g., "Flow Error: [Your Flow Name]"), Priority (e.g., "High"), and Status (e.g., "New") to help categorize the error.
Connect to Notification/Screen Elements:
From the "Create Case" element, you can then connect to further elements, such as:
- Email Alert Element: To notify an administrator or a specific user about the error, linking to the newly created Case.
- Screen Element: To display a user-friendly error message to the person running the flow, informing them that an issue occurred and that a support ticket (Case) has been created.

Using a Table to Summarize Fault Actions

Action Type	Description	Flow Element Example	Benefits
Log Error	Store detailed fault messages in a Salesforce record (e.g., Case, Custom Error Log Object).	`Create Records` (e.g., "Create Case" with `{!$Flow.FaultMessage}`)	Provides an audit trail for troubleshooting; centralizes error data.
Notify Administrator	Send an email or push notification to system administrators or a specific team when a critical error occurs.	`Send Email Alert`	Timely alerts for critical issues; proactive problem-solving.
Notify User	Display a user-friendly message on a screen flow, explaining that an error occurred and what steps to take next (e.g., contact support).	`Screen` with `Display Text` or `Text Template`	Improves user experience; avoids abrupt flow termination; guides users.
Rollback Transaction	For screen flows, if a DML operation fails, all previous DML operations in the same transaction are automatically rolled back, ensuring data integrity. For autolaunched flows, this is generally automatic.	No specific element; inherent to DML operations in a transaction.	Prevents partial data changes and ensures atomicity of transactions.
Re-attempt (Advanced)	Design an alternative path or retry logic for temporary failures (e.g., external service timeouts).	`Decision` + `Subflow` (with retry logic)	Increases resilience for transient errors.

Best Practices for Flow Error Handling

Be Proactive: Anticipate where errors might occur and add fault paths to those elements.
Log Everything: Always log the $Flow.FaultMessage to a standard or custom object. This is invaluable for debugging.
Provide User-Friendly Feedback: When a user-facing flow fails, don't just show a generic error. Use a Screen element on the fault path to explain what happened and what they can do next.
Notify Admins for Critical Errors: Use Email Alert to inform relevant personnel immediately about significant failures.
Keep Fault Paths Simple: The fault path should primarily handle the error, log it, and notify. Avoid complex business logic within the fault path itself.
Test Thoroughly: Test your fault paths by deliberately introducing scenarios that cause the elements to fail (e.g., attempting to create a record without a required field).
Use Subflows for Reusability: If you have a standard error logging or notification process, encapsulate it in a subflow and call it from multiple fault paths.

By diligently applying these error handling techniques, especially leveraging the $Flow.FaultMessage variable and creating records to log issues, you can significantly enhance the reliability and maintainability of your Salesforce Flows. For more details on global variables like $Flow.FaultMessage, refer to the official Salesforce Flow documentation.