During startup, if the download.cacheroot is not already setup by
the admin console from the web interface, which will be the case
for first time installation (a typical chicken-or-egg problem),
the setup tries to create a directory named 'download_cache' under
the home directory of the user starting up the tomcat process. It
looks like because of some permission issue, the HID startup
process cannot create that directory and since that directory does
not exists as the consequence raised the exception.