Multiple datasources in Jasper Report working only locally

[niki76]

Hello,
I need to fill a single report with data from two different databases.
I searched and found these instructions:
https://community.jaspersoft.com/wiki/how-use-multiple-data-sources-jaspersoft-studio-or-jasperreports-server
https://community.jaspersoft.com/wiki/multiple-datasources-ireport-lists-tables-and-subreports

So I followed them and I could get it to work locally, in Jaspersoft Studio.
When I deploy it on the JasperReports Server, though, it does not work, returning this error:

There was an error on the server. Try again or contact site administrators. (Error UID: c432759b-10a4-4b70-91b9-630f13281425)

I am running JasperReports Server 7.5.0, Build: 20191206_1440.
I searched the Community for hints, but I could not find what I wish for.

Here in attachment a simple report that (with the correct connection string, that I changed here for obvious reasons) works fine locally.

Thanks for your help.
Kind regards,
Niki
 

[niki76]

Solved

Got it: driver issue.
The client used a jdbc:jtds driver, not available on the server, which works using a jdbc-only driver.

I wish the error message was more meaningful, but that's it.

Kind regards,
Niki