J'ai eu le souci
tu trouves ces infos là :
http://flytec.com/software.html#usb"USB driver workaround for Windows 8 with older instruments
Windows 8 does not normally accept the driver necessary for older instruments. If you wish to use an older Flytec instrumen with W8, please use the following steps to install the necessary instrument driver. Please note that it may not be possible to update firmware using this driver in W8, in this case please contact Flytec USA or Flytec AG for assistance. Special thanks to Sérgio Da Silva for putting together the following procedure. Video instructions here
Install FlyChart or other flight software normally on the Windows 8 PC
Download Flytec Win8.exe and extract to a convenient location (e.g., desktop)
Connect Flytec Instrument to PC and let W8 install its driver
Open folder Flytec Win8 extracted in step 2 and right-click on PL-2303_Driver_Installer.exe and select Run as Administrator. Click Next and Finish
In the Flytec Win8 folder from step 2, open the folder corresponding to your version of Windows 8/8.1, either 32bits or 64bits. If you are uncertain, go to
http://windows.microsoft.com/en-CA/windows/which-operating-system to help you determine which version you have.
Right-click on install_32 or install_64 (depends on your version of W8) and and select Run as Administrator
Disconnect instrument and reconnect. Launch desired flight application (e.g., FlyChart ) and select the Prolific USB connection (e.g., FlyChart: Extras>System settings>Port> COM=Prolific USB
Important: Always use the same USB port for connecting the instrument.