Set up SAMBA Server, but can't access

Today I set up a SAMBA server to share files. I can connect to the server from the same network (e.i: a.b.x.). But when I am on another network (a.b.y.), I cannot connect to the server. Running smbstatus returns the following:


Samba version 4.2.4-21.3-3689-SUSE-SLE_12-x86_64PID     Username      Group         Machine            Protocol Version       
------------------------------------------------------------------------------
Failed to initialize session_global: NT_STATUS_ACCESS_DENIED


Service      pid     machine       Connected at
-------------------------------------------------------
Failed to initialize session_global: NT_STATUS_ACCESS_DENIED
Failed to traverse sessions: NT_STATUS_ACCESS_DENIED


No locked files

And there is nothing in /var/log/samba/log.smb file. The problem is not related to firewall (even if I turn off the firewall, I still get the same error).

And this is my smb.conf fie:


[global]
        workgroup = WORKGROUP
        passdb backend = tdbsam
       printing = cups
        printcap name = cups
       printcapcachetime = 750
        cups options = raw
        map to guest = Bad User
        include = /etc/samba/dhcp.conf
        logon path = \\%L\profiles\.msprofile
        logon home = \\%L\%U\.9xprofile
        logon drive = P:
        usershare allow guests = No
        security = user
        add machine script = /usr/sbin/useradd  -c Machine -d /var/lib/nobody -s /bin/false %m$
        domain logons = Yes
        domain master = Yes
        wins support = No
        usershare max shares = 100
        local master = Yes
        os level = 65
preferredmaster = Yes
        wins server =
[homes]
        comment = Home Directories
        valid users = %S, %D%w%S
        browseable = No
        read only = No
        inherit acls = Yes
[profiles]
        comment = Network Profiles Service
        path = %H
        read only = No
        store dos attributes = Yes
        create mask = 0600
        directory mask = 0700
[users]
        comment = All users
        path = /home
        read only = No
        inherit acls = Yes
        veto files = /aquota.user/groups/shares/
[groups]
        comment = All groups
        path = /home/groups
        read only = No
        inherit acls = Yes
[printers]
        comment = All Printers
        path = /var/tmp
        printable = Yes
        create mask = 0600
        browseable = No
[print$]
        comment = Printer Drivers
        path = /var/lib/samba/drivers
        write list = @ntadmin root
        force group = ntadmin
        create mask = 0664
        directory mask = 0775


[netlogon]
        comment = Network Logon Service
        path = /var/lib/samba/netlogon
        write list = root


[Shared]
        guest ok = Yes
        inherit acls = Yes
        path = /home/myusername/Shared
        read only = No


I spent more than 5 hours but I could not solve it. Any help is appreciated.

I talked to network administrator. The routers were blocking SMB ports.