KB20393: ‘The user is required to specify an answer for this prompt. The prompt's designer specified that the prompt must be answered but did not supply a default answer’ is reported in the DELogs after running services in MicroStrategy Narrowcast Server

SYMPTOM:
When a standard Strategy Narrowcast Server 8.x service or one of the Web Deliveries services are run, the following error is reported in the DELogs:
CAUSE:
One possible cause for this error is that the report linked to the Information Object in the service (if it is a standalone Strategy Narrowcast Server 8.x service) or the subscribed report (if it is a Web Deliveries service) has been modified to include one or more required prompts. These prompts do not have a default answer set. Since this report did not contain the prompt(s) originally, Strategy Narrowcast Server 8.x does not have any prompt answers to pass to the Strategy Intelligence Server 8.x. as required.
ACTION:
If the report is part of a standalone Strategy Narrowcast Server 8.x service:

• Edit the required Information Object to refresh the report definition
  
• If the Information Object is in a Strategy Narrowcast Server 8.x document, edit the document, and then edit the Information Object as shown:
  

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  This refreshes the report definition in the Information Object. Click Finish in the Information Object Wizard window.
  
  

• If the report was directly added to the service from the Service Wizard (i.e. linked report), edit the service using the Service Wizard, go to the Message contents tab, and edit the attachment.
  
  

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  Click on the Refresh button as shown:
  
  

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  This should update the report definition. Click OK.
  
  

• Edit the subscription set to specify the necessary prompt answer(s) for the subscriber(s), as shown:
  

If the error occurs for a Web Delivery service, the subscribed user(s) must edit the subscription and specify the necessary prompt answer(s) to resolve the issue.