This can be a pain when you want to remove old drivers for a device that is not working.
People also do not realise that installing the same device in a different USB port installs new device instance.
This is why when you have NO Serial ports but when you install one it sets up as COM9 as you have 8 hidden com ports in device manager.
to see hidden devices you need to set environment variable "devmgr_show_nonpresent_devices" equal to 1
you could do at command prompt (run as admin)
or if you want it permanent then add to a system environment variable
In device manager go to VIEW and select SHOW hidden devices.
you can then see them grey... and you can edit and remove them
Also good for removing old devices when you upgrade a motherboard or graphic card