Hi Vianney,
Hmmm, I’ve tried running the 2.27 installer, but I get message per red box below. Per message, if we reboot our HL7692, nothing seems to happen. Ditto if we don’t reboot. After a minute, we see the messages below the red-boxed. And then per the last message, the prompt closes after a further 5 seconds 
The HL7692 is connected to my PC on COM7, comspec 115200 N81. AT command communication works fine on COM7, using a terminal emulator.
I’ve tried the installer with the HL7692 freshly booted, after waiting the 13.2 seconds for it to boot. I’ve also tried the installer after issuing a few AT commands.
I’ve googled a bit, and found this post: Dev kit HL8548-G firmware
Taking the hint cue from that post, I typed %APPDATA% in my Windows Explorer, takes me to folder C:\Users\dking\AppData\Roaming\
I then created there, an HL76xx_download.ini file, containing:
[CommPort]
Port=COM7
ComBaud=115200
Per the Dev kit HL8548-G firmware, noted that the ComBaud line might be ignored, and 115200 is used always.
Unfortunately, this guessed solution didn’t work. Ditto, if I tried instead filename HL7692_download.ini
As mentioned, our HL7692 presently has 2.23 firmware, which is what it came with. FWIW, I tried the 2.23 installer. Same sorry story.
I’m presently out of ideas !
Best regards,
David