I just bought an RG405M and heard so many good things about upgrading to GammaOS that I thought I would try. I followed this video guide:

https://www.youtube.com/watch?v=BD0ab1gr4gM&ab_channel=RetroGameCorps

​

And everything was going perfectly until 10:03 where it's supposed to boot up into GammaOS. But my device just stayed on the boot screen with the message:

​

INFO: LOCK FLAG IS : UNLOCK!!!

WARNING: LOCK FLAG IS : UNLOCK, SKIP VERIFY!!!

​

Googling only returned one helpful result, from this very subreddit:

https://www.reddit.com/r/ANBERNIC/comments/14dvnu6/bootloop_after_reboot_to_recovery_gamma_os/

​

/u/The_Gamma_Squeeze commented on the video in that post to say the problem was probably caused by the SD card being in the slot when following the procedure. The instructions now say to remove your SD card before doing this - but stupidly, I was blindly following the video guide and did not check each step in the written guide. My own fault, obviously, but now struggling to get my device working at all.

​

The suggested fix is to follow the unbricking guide:

https://www.youtube.com/watch?v=fT6kulEfWXo&ab_channel=TheGammaSqueeze

​

The video starts at a later stage than the written instructions in the README file, and the first few steps that are not covered in the video is where I am having trouble.

1. Turn off your RG405M and make sure the USB cable is unplugged.

2. Open the Device Manager on your Computer.

3. Hold down the Home/Back combo button on your RG405M and plug it into your Computer while the button is held down.

4. A new device will appear in your Device Manager, right click it and click on "Update driver", then "Browse my computer for drivers", then "Browse...", pick the included "Drivers" directory and tick "Include subfolders" before hitting "Next" and finally "Close".

5. Double-click "UpgradeDownload.exe".

6. Click on "OK" if you get a "Get MAC Address Fail!" window.

7. Click on the "Load Packet" button (the single cogwheel) and choose the included "Firmware.pac" file inside the "Firmware" directory.

8. Click on the "Start downloading" button (the right-pointed arrow) and the flashing procedure should begin.

9. About 4-5 minutes later your device should be back on Anbernic's V1.15 stock firmware.

​

Step 4, from what I can see, nothing new appears in Device Manager. Does anyone know what the device name would be? I also tried the "Add Device" feature from Windows there, but also no luck.

​

Any advice greatly appreciated.