This exception occurs if the tests did not run due to some error on the jenkins slave. The error on the jenkins slave was my fault, so don't care about this.
I think this is because there is no result to archive if the tests were started but did not run.

ERROR: Publisher com.michelin.cio.hudson.plugins.qc.QualityCenterResultArchiver aborted due to exception
java.lang.NullPointerException
at java.io.File.<init>(Unknown Source)
at com.michelin.cio.hudson.plugins.qc.QualityCenterResultArchiver$1.invoke(QualityCenterResultArchiver.java:104)
at com.michelin.cio.hudson.plugins.qc.QualityCenterResultArchiver$1.invoke(QualityCenterResultArchiver.java:94)
at hudson.FilePath$FileCallableWrapper.call(FilePath.java:1994)
at hudson.remoting.UserRequest.perform(UserRequest.java:118)
at hudson.remoting.UserRequest.perform(UserRequest.java:48)
at hudson.remoting.Request$2.run(Request.java:287)
at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source)
at java.util.concurrent.FutureTask.run(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)