uninstall leaves Registry Keys behind

[John Ludwig]

When com0com is removed/uninstalled from SOME (not all) machines, it will occationally
leave behind some of the registry keys

When things are installed properly, the following keys exist in the registry:

HKLM SYSTEM\CurrentControlSet\Enum\com0com\                         port\                         CNCA0\
                            Control
                            Device Parameters
                            logConf
                           
HKLM SYSTEM\CurrentControlSet\Enum\com0com\                         port\                         CNCB0\                             Control
                            Device Parameters
                            logConf

After a successful uninstall only one high-level key remains:
HKLM SYSTEM\CurrentControlSet\Enum\com0com\

The problem is that for some reason, on a few machines, the uninstall leaves behind
a partial key:

HKLM SYSTEM\CurrentControlSet\Enum\com0com\                         port\                         CNCA0\
                            logConf
But the rest of the keys have been removed.

This left-behind key cannot be manually removed without manually changing the permissions.

Because of a company wide requirements for complete uninstalls, we can NOT leave these registry keys
behind on a PC after an uninstall has supposed to have been performed.

Do you know a cause of why these registry keys could be left behind?
Is there a fix for this condition?? Is this a known bug to uninstalling com0com?
Is there a work around for this?

Any help would be greatly appreciated