The error message is 'failed to retrieve share list from server' so it cannot browse a Windows 7 pc or a Ubuntu 10 pc or a mac desktop pc.
smbtree lists all the shares from machines on the network
so off to /etc/samba and we sudo pico smb.conf
The name resolve order uses hosts files first and broadcasts last and it is commented out! Maybe we change that to:
name resolve order = bcast host
and then restart the servers with service smbd restart and service nmbd restart
Works! This is an awful mistake to make in an upgrade. Upgrade should not break what is working, particularly something as important as networking. Good thing i recall the manual work you had to do to get samba working back in redhat 5 and 6.