Why can't I re-install vCenter Orchestrator?

When trying to re-install vCenter Orchestrator (vCO), there is occasion when a file prevents the re-installation of the product. The following error may be experienced:

Found the same version of vCenter Orchestrator (x.x.x.xxx). To reinstall this version of the product, first uninstall the current version and run this installer again. You can export the current configuration from the Web Configuration interface and import it back into the product after you have completed the new installation

The solution is to remove the following file:
C:\\Program Files\\Zero G Registry\\.com.zerog.registry.xml
or
C:\\Program Files (x86)\\Zero G Registry\\.com.zerog.registry.xml

On OSX, this file is a little harder to find:

~/Library/Preferences/.com.zerog.registry.xml (HIDDEN)

And for Linux: (Thanks George Dimitrov !)

/var/.com.zerog.registry.xml
or
/home/user/.com.zerog.registry.xml