So heres the solution from FTDI Ltd Support:
The uninstaller was broken by windows update KB923191. The workaround is to
go to the system 32 folder, right click on the ftdiunin.exe to bring up the
In this window select the compatibility tab and change mode to windows 2000.
Now run the uninstaller.
This works perfectly
I did the same to the FTDIUNIN.exe in the FTDI USB Drivers install folder. So now when i reinstall the drivers it installs the modified uninstaller. So than i can uninstall just fine.