From: John Beckett 

"Rich"  wrote in message news::
>      On Windows 2000 and Windows XP UDP port 445 is opened but I don't
> think it is used or don't know how if it is.   On Windows Server 2003
> UDP port 445 is not open.  Look at
> http://support.microsoft.com/default.aspx?scid=kb;en-us;832017 and
> you'll see that TCP 445 is mentioned but UDP 445 is not.  The Windows
> Firewall in Windows XP and Windows Server 2003 also associates TCP 445
> only with SMB.

I just ran
netstat -ano | find ":445"
on a Windows Server 2003.

Output showed:
  TCP    0.0.0.0:445     0.0.0.0:0        LISTENING       4
  UDP    0.0.0.0:445     *:*                              4
so it appears that 445/udp is in use (and by the same process as 445/tcp,
namely System).

John

--- BBBS/NT v4.01 Flag-5