Released over a decade ago, iReport 4.0.1 hit a sweet spot for stability. It was the version just before major architectural shifts that broke compatibility with older Java environments. Many developers stick with 4.0.1 because:
Since your request is ambiguous, here are possible interpretations: jaspersoft ireport designer 4.0.1 download
iReport Designer is a desktop report authoring tool built to create JasperReports templates (.jrxml). Version 4.0.1 is an older but stable release from the 4.x era that introduced improvements in layout controls, report parameters, subreports and compatibility with certain JasperReports library versions. It was widely used for rapid report prototyping and integration into Java applications and enterprise reporting workflows. Released over a decade ago, iReport 4