Samba cannot resolv ip

Are you using opendns?

Regards
chuck

No, i'm using my provider's dns servers...

What is the output of:
$ nslookup pc-chiara

Can you ping pc-chiara without putting the IP in /etc/hosts ?

Also
- Does using "-R bcast" option in smbclient help ?
- Please send the output of the smbclient failure with "-d4" debug level.

nslookup PC-CHIARA outoput:

Server: 192.168.1.1
Address: 192.168.1.1#53

Non-authoritative answer:
Name: pc-chiara
Address: 195.210.87.131

"smbclient -R bcast -L pc-chiara" output:

timeout connecting to 195.210.87.131:445
timeout connecting to 195.210.87.131:139
Connection to pc-chiara failed (Error NT_STATUS_ACCESS_DENIED)

"sbmclient -d4 -L pc-chiara" output:

lp_load_ex: refreshing parameters
Initialising global parameters
params.c:pm_process() - Processing configuration file "/etc/samba/smb.conf"
Processing section "[global]"
doing parameter workgroup = WORKGROUP
doing parameter server string = %h server (Samba, Ubuntu)
doing parameter wins support = yes
doing parameter dns proxy = no
doing parameter name resolve order = lmhosts wins bcast host
doing parameter log file = /var/log/samba/log.%m
doing parameter max log size = 1000
doing parameter syslog = 0
doing parameter panic action = /usr/share/samba/panic-action %d
doing parameter encrypt passwords = true
doing parameter passdb backend = tdbsam
doing parameter obey pam restrictions = yes
doing parameter unix password sync = yes
doing parameter passwd program = /usr/bin/passwd %u
doing parameter passwd chat = *Enter\snew\s*\spassword:* %n\n *Retype\snew\s*\spassword:* %n\n *password\supdated\ssuccessfully* .
doing parameter pam password change = yes
doing parameter map to guest = bad user
doing parameter usershare allow guests = yes
pm_process() returned Yes
added interface wlan0 ip=fe80::221:6bff:fe39:c5bc%wlan0 bcast=fe80::ffff:ffff:ffff:ffff%wlan0 netmask=ffff:ffff:ffff:ffff::
added interface wlan0 ip=192.168.1.111 bcast=192.168.1.255 netmask=255.255.255.0
Client started (version 3.3.2).
tdb(unnamed): tdb_open_ex: could not open file /var/run/samba/gencache.tdb: Permesso negato
Connecting to 195.210.87.131 at port 445
timeout connecting to 195.210.87.131:445
Connecting to 195.210.87.131 at port 139
timeout connecting to 195.210.87.131:139
Error connecting to 195.210.87.131 (Operazione già in corso)
Connection to pc-chiara failed (Error NT_STATUS_ACCESS_DENIED)

At the moment of these attempts, the local ip of pc-chiara is 192.168.1.3

Thank you very much for your help :)

Your machine resolves pc-chiara as 195.210.87.131 so it's quite normal that samba cannot connect to it. You probably can't ping it either. This is not a samba bug, more an issue in configuration of your name resolution... You should be able to work around the issue by adding pc-chiara in your /etc/hosts file ?