I just installed the latest version of sonarqube on my server and did a test run on my project with the sonar-scanner executable. This works.
In the next step, i'm creating a new VSTS Build Definition with the existing SonarQube build steps.
When I trigger this build, it fails in the last step, after the report has been uploaded to my SonarQube server:
I don't know why this happens, because the sonar-scanner is working just fine. I'm using the same parameters in my MS Build step.