When parsing fxCop results (fxcop 1.35), I get following error (see lower). The same file is parsed by Violation plugin without errors.

note: when the fxCop results are parsed from console, it caused the whole build process to fail, when the results are parsed from an fxCop_output.xml, the build finishes correctly and this error is just a warning in cosole output

I can provide the fxCop output, but rather not publicly...

[WARNINGS] Parsing warnings in console log with parser FxCop
ERROR: Publisher hudson.plugins.warnings.WarningsPublisher aborted due to exception
hudson.util.IOException2: Content is not allowed in prolog.
at hudson.plugins.violations.types.fxcop.FxCopParser.parse(FxCopParser.java:57)
at hudson.plugins.warnings.parser.ViolationsAdapter.parse(ViolationsAdapter.java:60)
at hudson.plugins.warnings.parser.ParserRegistry.parse(ParserRegistry.java:321)
at hudson.plugins.warnings.parser.ParserRegistry.parse(ParserRegistry.java:300)
at hudson.plugins.warnings.WarningsPublisher.parseConsoleLog(WarningsPublisher.java:286)
at hudson.plugins.warnings.WarningsPublisher.perform(WarningsPublisher.java:234)
at hudson.plugins.analysis.core.HealthAwarePublisher.perform(HealthAwarePublisher.java:338)
at hudson.tasks.BuildStepMonitor$1.perform(BuildStepMonitor.java:19)
at hudson.model.AbstractBuild$AbstractBuildExecution.perform(AbstractBuild.java:717)
at hudson.model.AbstractBuild$AbstractBuildExecution.performAllBuildSteps(AbstractBuild.java:692)
at hudson.model.Build$BuildExecution.post2(Build.java:183)
at hudson.model.AbstractBuild$AbstractBuildExecution.post(AbstractBuild.java:639)
at hudson.model.Run.execute(Run.java:1485)
at hudson.model.FreeStyleBuild.run(FreeStyleBuild.java:46)
at hudson.model.ResourceController.execute(ResourceController.java:88)
at hudson.model.Executor.run(Executor.java:239)
Caused by: org.xml.sax.SAXParseException: Content is not allowed in prolog.
at com.sun.org.apache.xerces.internal.parsers.DOMParser.parse(Unknown Source)
at com.sun.org.apache.xerces.internal.jaxp.DocumentBuilderImpl.parse(Unknown Source)
at javax.xml.parsers.DocumentBuilder.parse(Unknown Source)
at hudson.plugins.violations.types.fxcop.FxCopParser.parse(FxCopParser.java:45)