BPM 12c: Error when trying to start JDeveloper - Could not install some modules

When trying to start JDeveloper for SOA 12c or BPM 12c you may encounter the following error:

Warning - could not install some modules:
oracle.external.timing - org.netbeans.InvalidException: Netigso:
C:\Oracle\MiddlewareBPM\Oracle_Home\jdeveloper\external\oracle.external.timing.jar: Not found bundle:oracle.external.timing oracle.jdeveloper.webservice.share - org.netbeans.InvalidException: Netigso

To fix this error and start JDeveloper do the following:

- Delete all folders and files under:
  C:\Users\{user}\AppData\Roaming\JDeveloper

After that JDeveloper should start without error.