This is a fake sox-path :-) You must use ure own path!!! Where is your sox. exe? Or do you start the batch file or command inside the folder of Sox, where the sox.exe is?

This should work - commandline (if you have flac inside):
FOR %F IN (*.wav) DO sox.exe "%F" -b 8 "%~NF.flac"

Or in a *.cmd:
FOR %%F IN (*.wav) DO sox.exe "%%F" -b 8 "%%~NF.flac"

Regards
Thomas

Am 27.05.2020 um 11:48 schrieb Nils Wallgren:

“C:\sox.exe"' is not recognized as an internal or external command”