A delivery for a BI 4.x WebI document was created in the legacy Flash user interface. The delivery format is "Excel". The following error occurs when attempting to open that delivery in the HTML5 user interface:
Excel (.xls) for BI 4.x Webi is not supported in this UI. Would you like to delete it?
The error occurs because the .XLS format was omitted from the HTML5 UI. This issue is under investigation.
This issue is resolved in Build 240 FP3. The .XLS format has been added to the HTML5 UI.
In Build 240 FP2, this issue manifests as a prompt when attempting to open a BI 4.x WebI Excel (.xls) asking to delete or keep delivery.