LBI report linked to Excel file

Has anyone successfully linked an Excel file to a published LBI report?

We regularly use Crystal Reports linked to an Excel file to help pull reports for a specific set of items. We populate the Excel file with the list of items and then run the file which is linked by the field.

I've been trying to publish a report to LBI that would allow our end users to populate an excel file and then run a report off LBI (avoiding the need to have Crystal Reports but giving them the flexibility to run more efficient reporting).

When I try to run the published Crystal report, it gives an error for the credentials of the Excel Lookup file. I've input the username and password for the database source and even tried using the same credentials to populate the data setting for the lookup file, but still getting the error.

Any thoughts?