As FTK 2 was not yet installed there was no need to uninstall it, but Oracle needed to be uninstalled. However this was problematic, because despite using the Windows Add/Remove Programs option and Oracle appearing to be uninstalled Oracle was still left in the Start Menu, Programs files, and registry, much like a virus or Adware. To make matters worse, a new version of Oracle could not be installed until the old one was removed. For this reasons repeated attempts were made to remove Oracle, in the same way a virus would be; killing the processes, deleting the registry entries, deleting the programs files, rebooting, and starting again.
After about 30 minutes or so Oracle appeared to be removed and FTK 2 could be installed.
But it was only after manually removing the registry entries, killing the processes, and removing the files manually that the FTK 2 installer asked if it could “uninstall oracle” – during the install option!
This option was dutifully followed, then there were a few more restarts and then the Oracle installation was tried again. But this lead to a completely new error shown during the installation “Error ID: -505”
Once again googling this brought a complete blank.