you have to access it via terminal.
-Go to Launchpad > search Terminal, then open it
-sudo nano /etc/nsmb.conf
-Paste this in there,
[default]
signing_required=no
streams=yes
notify_off=yes
port445=no_netbios
protocol_vers_map=4
soft=yes
dir_cache_off=yes
dir_cache_max_cnt=0
mc_prefer_wired=yes
mc_on=no
-Save and Exit, then reboot MAc.
