Was unable to use the Windows app to update either the guitar or dongle for my Xbox edition controller. Clicking either the "Guitar" or "Wireless Receiver" button would just result in the app crashing after a second or two. Looking at event logs it's missing the x86 version of MSVCP140.dll.
The fix was installing the Microsoft C++ 2015-2022 x86 Redistributable: https://aka.ms/vs/17/release/vc_redist.x86.exe
After installing and rebooting, the Firmware updater no longer crashed, and I was able to update both the guitar and dongle. Hope this helps somebody else.
