Samba problems

Suddenly (at least I cannot remember any change) I cannot use the Network server with samba as I get the following message

Impossible to show smb:/// as Nautilus cannot contact SMB master browser.
Please check if a SMB server is operating on local network

And here are results of a testparm.....

[root@Contec antoniomontagnani]# testparm
Load smb config files from /etc/samba/smb.conf
Processing section "[homes]"
Processing section "[printers]"
Processing section "[Aurat]"
Loaded services file OK.
Server role: ROLE_STANDALONE
Press enter to see a dump of your service definitions

# Global parameters
[global]
       server string = PC Antonio
       null passwords = Yes
       username map = /etc/samba/user.map
       log file = /var/log/samba/%m.log
       max log size = 50
       socket options = TCP_NODELAY SO_RCVBUF=8192 SO_SNDBUF=8192
       os level = 10
       dns proxy = No
       guest ok = Yes
       hosts allow = 192.168.0.0/24

[homes]
       comment = Home Directories
       read only = No

[printers]
       comment = All Printers
       path = /var/spool/samba
       printable = Yes
       browseable = No

[Aurat]
       comment = Copia directory HP
       path = /home/antoniomontagnani/HP
       read only = No

--
Antonio Montagnani
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Working with Mozilla 1.6 on Linux Fedora Core 1
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  Utilizzo Mozilla 1.6 su Linux Fedora Core 1
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