This solution does not work. the problem is not a configuration problem. In fact, CF Flasher does not use the right library to drive the USB Multilink with a USB 2.0
To correct the problem, the unit_cfz.dll file, placed in \Windows\System32\ should be replaced by a new one (in version 3.14 instead of 3.13).
This new dll is put in attachment.
Thanks for your answer.