If your server runs or 7.5 , version 6.12.2 of Studio is the perfect match. Newer Studio versions (7.x+) often introduce newer JRXML syntax that your older server cannot parse, causing failed uploads.

Hardware Requirements Jaspersoft Studio needs a 64-bit processor and at least 500 MB of hard disk space. Jaspersoft Community Previewing a Report - 10.0.0 - Jaspersoft Community