You’ve just updated your Raspberry Pi (or whatever Linux) and you’re noticing your CIFS (smb) mounts aren’t getting auto mounted anymore. You curse and start noticing this error:

# mount -t cifs //192.168.1.100/public -o username=public,password=public sam/ mount error(13): Permission denied Refer to the mount.cifs(8) manual page (e.g. man mount.cifs)

The solution is to add after -o username=X,password=Y the following: sec=ntlm; thus it becomes -o username=X,password=Y,sec=ntlm.

You can do the same in fstab:

//192.168.1.100/public /mnt/sam/ cifs domain=TIETE,username=public,password=public,sec=ntlm 0 0

No idea why it’s suddenly required, but whatevs.