In my previous post SFDC Flow: Add a Custom Button , we learn how to add a custom button to launch an SFDC flow. Now we have one more final step for SFDC flows is to add a fault Screen. This is an optional step.

Add a Fault Screen

If an error occurs while the flow is interacting with the database, the flow displays a generic unhandled fault message. The system sends the organization administrator an email with information to help identify the issue. You can also set up fault paths to a screen that displays this information to the flow user. Instead of waiting for a system message to reach your email account, you can view the information in the flow and immediately fix the problem.

1.  Reopen the flow if necessary.

2. From the Palette tab, drag the Screen onto the canvas.

    The Screen overlay opens with the General Info tab selected.

3. For the Name, enter Fault Screen.

   The Unique Name is automatically populated based on this entry.

4. From the Add a Field tab, double-click Display Text.

5. Click [Display Text] in the preview pane.

6. On the Field Settings tab, configure the field as follows.

    Field                           Value

    Unique Name          fault_message

    text box                     Sorry, an error occurred in the flow.

                                       For help, provide your flow administrator with the

                                       following -

                                       information: {!$Flow.FaultMessage} 

7. Click OK.

8. Connect both the Record Create and Record Update elements to the fault screen.

a. Drag the node from the bottom of the Record Create element onto the new Screen element.

b. Drag the node from the bottom of the Record Update element onto the new Screen element.

Notice that these new connectors have “FAULT” labels.

9. Click Save.

10. Click Close.

Now, if the flow encounters a validation rule or error, the flow user sees a meaningful error message instead of the generic unhandled fault message.

If your flow is already working fine, you can still test the fault screen by entering a value that would fail the validation rule you created in an earlier tutorial. Specifically, while running the flow, enter a Quantity Ordered value that’s obviously greater than the quantity available for the merchandise.

**This document is referred from salesforce help tutorials