Can't see/mount SMB (SAMBA 4) shares through terminal in Debian Jessie

Question

I would like to mount a SAMBA share on my computer, where I'm running Debian 8 (Jessie). The SMB share is located at the server of my institute and works as a domain controller (it's a SAMBA 4). All machines are located inside the private network of the institute.

I can see and mount the shares from a OSX 10.9.5 with:

smbutil view //<user_name>@<server_domain_name>/share

and:

mount_smbfs //<user_name>@<server_domain_name>/share ~/my_share

From my computer, I can access the share via nautilus (GNOME nautilus 3.14.1), through the "Connect to Server" option at the sidebar, with:

• smb://<server_domain_name>/share as Server Address
• <user_name>@<domain> as the username
• <domain>.es as the domain

However, it gives me the following error when using the command-line:

sudo mount.cifs //<server_domain_name>/share ~/my_share -o user=<user_name>@<domain>,workgroup=<domain>.es

mount error(13): Permission denied Refer to the mount.cifs(8) manual page (e.g. man mount.cifs)

I have tried removing the @<domain> part from the user, adding a $ at the end of the server address (//<server_domain_name>/share$), but everything has been unsuccesful.

When I try to connect to the server with smbclient, it gives me another error:

smbclient  //<server_domain_name>/share --user=<user_name>@<domain> --workgroup=<domain>.es
Enter<user_name>@<domain>.es's password: 
session setup failed: NT_STATUS_LOGON_FAILURE

And I get the same error with:

smbclient -L //<server_domain_name>/share -U <domain>/<user_name> -W <domain>.es

It seems to be a Linux-related issue, since it works for OSX but not for Debian (I also tried up in Ubuntu and it did not work). Have I overlooked anything? I am unable to find a solution to this issue and I have been struggling with this more than two weeks...

I would appreciate some hints/comments about this, since I am aware I am not the only one person experiencing this, and after trying multiple apparent solutions from many forums, I still haven't found the right one.

Thanks in advance