There were a few important points not documented in the “Beta TinyBooter Update Procedure” on this page…
I recommend replacing those instructions with this…
[quote]The following steps are necessary to update the G400 Beta TinyBooter:
Copy the newest TinyBooter into the G400 Beta Programmer folder.
Put the G400 into bootloader mode by grounding PA11 and powering up the mainboard (do not hold pin PA11 to ground no longer than 3 seconds or damage may result to the mainboard). You will see the bootloader titled “GPS Camera Detect (COMx)” in “Devices and Printers” or “Device Manager”. From there, you will need to locate the COM port number.
Right-click on the CommandPrompt.bat file and choose “Run as Administrator” to load the command prompt or manually run the command prompt from the Run menu. If it does not open to the “G400 Beta Programmer” folder you will need navigate to it using the “CD” command.
At the command prompt, type ProgramG400 COMx (x being the COM port that the bootloader selected; NOTE - COM needs to be typed in all caps) and press enter.
Wait till the process is complete. A log file will appear when the process is complete.
Reset the board and you are ready for the Firmware Update Procedure.[/ul][/quote]