Sonar >> Troubleshootings
After a SonarQube Scanner has finished analyzing the code, the Analysis Report is sent to SonarQube Server. If a failure message is returned, verify the error log on the server, see https://docs.sonarqube.org/display/SONAR/Background+Tasks
A possible problem is that the maven project has the same key (groupID:artifactID) than an existing project analyzed by Sonar