G1 not updating
TT350 users found this one out the hard way when Adorama mistakenly posted the TT350-C update (specifically for adding compatibility with some newer EOS M bodies) as a generic TT350 update.
So many non-Canon TT350 owners bricked their flashes with this update, Godox eventually posted the initial versions of the TT350 firmware.
Make sure you're using the correct cable for the device.
Newer devices (e.g., A1, Xpro, R2 Pro II, AD400 Pro, X2T) use a USB-C cable, while older devices (e.g., TT685, V860II, AD200) use a micro USB cable.
Check the Godox downloads page to make sure you're using the correct application for your device.
Both applications, when installed, should also install a custom USB driver.
Also to make things just a little more interesting, the current Godox firmware download page – only available in Chinese language.
So Google Translate or similar will be needed to find the correct files (the Google Chrome browser is also very handy for fast translations).
Each device has its own separate firmware file for a reason.
I have my helix 12 linked to my 1199 and I can no longer get si on my 1199.
I’ll need to back up the update unless someone has a solution.
Or you can use the latest version of the open source 7Zip.
Someone on dpreview mentions that you may also need to disable driver signing to get the updater to work. Because it has attracted low-quality or spam answers that had to be removed, posting an answer now requires 10 reputation on this site (the association bonus does not count).