When an end user requests a report which is not a simple list report but the request is for a CSV format in the Web Portal, and they select parameters that result in no data being returned in the report, they receive a completely empty CSV file.
Applying the hotfix for defect ID 33261 from Knowledge Base article 328312, Header missing for subscribed CSV reports, does not resolve this issue.
Since the generated report is not a simple list report (e.g. isListReport = false), the generated step to generate the report in the process to send the report as email (E.g. RPS_RPSSubscription_Send_Report) is the "generate Report" step instead of "Export CSV" step. Since the hotfix for defect ID #33261 is to address the missing header issue caused within "Export CSV" step only, this hotfix is not applicable for this issue.
The a cause of of this issue is due to another product defect tagged under #33971.
This will be fixed in a future release of the product. If you require this immediately corrected, please contact Support for a hotfix referencing the defect ID 33971. Please note that the hotfix for this defect is implemented for version 8.1.4 and was tested to be working on version 8.1.3 only.