sudo mount -v -t cifs -o username=myname,password=mypassword //nas/share /mnt/nas

mount.cifs kernel mount options: ip=192.168.1.150,unc=\nasshare,user=myname,pass=********
mount error(95): Operation not supported
Refer to the mount.cifs(8) manual page (e.g. man mount.cifs)

# modprobe cifs
# echo 7 > /proc/fs/cifs/cifsFYI
# mount... etc.
# dmesg

CIFS VFS: Dialect not supported by server. Consider specifying
vers=1.0 or vers=2.1 on mount for accessing older servers