When generating aggregated reports with the jxr-plugin, the xref links cannot be generated correctly on windows. This is mainly due to the fact that the outputDirectory is a java.lang.String property in stead of a java.io.File property. This makes the propert os dependant. The expression with this property is ${project.build.directory}/site. On windows this should be ${project.build.directory}\site. It might even be beter to change it to ${project.reporting.outputDirectory}. See the checkstyle plugin for reference. When working with aggregated jxr-reports, the xrefLocation (which IS a java.io.File property) should preferable be ${project.build.directory}/site/../xref-test, since this is the relative publish location of the reports. Being a java.lang.String property, this will resolve to something like c:[path to build directory]\target\site\..\xref-test. In the SurefireReportMojo.determineXrefLocation the absolute path of this file property is compared to the outputDirectory which is a java.lang.String it will probably be set to c:[path to build directory]\target/site (n.b. forward slash in stead of backward slash), which will lead to an empty relative path, where ../xref-test would be expected.