Yes in windows
i reinstalled windchill 12.0, and tried to install flexplm and it shows this error
I just delete the top level folder along with WindchillDS, Tomcat and HTTP (apache).
In your username folder (c:\users\<name>)\Appdata there are a couple of PTC folders. One under Local and another under Roaming.
I then reboot and run regedit to remove any traces of my PTC loadpoint, e:\PTC in my case.