Updating to 4.20 - Service will not start

[christopher_parkin_directtradeltd_co_uk]

When upgrading our Jira Service Management software, I am getting through the guide as normal and when clicking finish and start JIRA, there is no response or any services started.

I tried using the .bat files but it seems the system variables are not there after be uninstalled when upgrading.

I have rolled back to previous version now but I can recreate this issue again when trying to update