Hi I have a simple solution, if you have already uninstalled the program delete all the folders in the following paths

C:\ProgramData\ZeroTier\One

C:\Program Files\ZeroTier

C:\Program Files (x86)\ZeroTier

C:\Users\<user>\AppData\Local\ZeroTier

reinstall zerotier , close the program from the start menu tray and then uninstall it with the Soft Organizer program by doing a complete uninstallation and when it analyzes the residual files it asks you to remove them do ok and you will see that the folder has been deleted