External Excel data source not refreshing upon report execution

[Ottiram]

Hello,

I have a problem with a standard RS report that uses an Excel file as external data source.
Changes / updates in the Excel file are not reflected when the report is executed via Cognos Connection. The only way to reliably make changes in the Excel appear in the report is to open it in RS, select the file and explicitly re-publish it. This is not something that I want my users to have to do, of course.
I tried the "Allow server to automatically load file" option, but with no consistent result.

Thanks for any hints you can provide!