[Samba] WinXP print problem

[Jean Lee]

Hello,

I am using samba to acces a printer on my Linux server from Windows XP 
Home SP2 clients.
It was working very well until yesterday evening. Since yesterday, I can 
print from the server (with cups) but I can't print from the Windows 
clients.
And all the shared folders are still OK. There is only printing from 
Windows clients which doesn't work.
We changed nothing on the server neither on the client side.

When I try to print a test page from Windows, I get the following error:
Unable to create a print task

I tried the following things :

Uninstall then reinstall printer from the windows client
Uninstall then reinstall printer from the server
reboot the server

I always have the problem

Here is a part of my /etc/smb.conf

[printers]
    comment = All Printers
    valid users = user gp pm cm
    path = /var/spool/samba
    browseable = no
# Set public = yes to allow user 'guest account' to print
    public = no
    writable = no
    printable = yes

I don't know where to search. I tried Ethereal but it is to complex for me.

Does anybody experienced this problem ? If no, where and what can I 
start to search ?

THank you for any help,

Jean Lee