can’t set the locale; make sure $LC_* and $LANG are correct

Comment out following line:

# on macOS Sierra edit file: /etc/ssh/ssh_config
# on previous versions, it should be located inside: /etc/ssh_config

# make sure to comment out this line
# inside this file you probably have

SendEnv LANG LC_*

# and you want to have something like this

# SendEnv LANG LC_*