An existing index lock was found.
An index lock file was found unexpectedly. This occurs either because JIRA was not cleanly shutdown
or because there is another instance of this JIRA installation currently running. Please ensure that no
other instance of this JIRA installation is running and then remove the following lock file(s) and restart JIRA:
Once restarted you will need to reindex your data to ensure that indexes are up to date.
Do not delete the lock file(s) if there is another JIRA running with the same index directory,
instead cleanly shutdown the other instance.