I have looked at the other posts and have made certain that the path is correct to the executable file, as shown below. I can launch git from from this path outside of Android
default path of git.exe for GitHubDesktop 64-bit version is
c:\Users\AppData\Local\GitHubDesktop\app-<version>\resources\app\git\cmd\git.exe
you should try this path.
This is the path where GitHub is located in its default installation. Remove the text including "<>" characters in below path and enter your relevant values.
c:\Users\<Your Windows username>\AppData\Local\GitHubDesktop\app-<version>\resources\app\git\cmd\git.exe
in windows 10, 64bit version your installed git location is C:\Program Files\Git, There is a bin folder inside Git folder and there is a git.exe file, this is the file you have to choose or add in android studio.Works for me.