[Samba] [smbclient] Fails sending pop-up message with -M

[Jeremy Allison]

On Wed, Sep 29, 2021 at 05:03:54PM +0200, Gilles via samba wrote:
>Hello,
>
>From Debian 9 running Samba 4-5-16, I'd like to send a pop-up message 
>to a Windows (7) host, but none of the following works:
>
>smbclient -M \\WIN-PC "test"
>smbclient -M //WIN-PC "test"
>smbclient -M ////WIN-PC "test"
>smbclient -M '\\WIN-PC' "test"
>
>Would someone have a working example?
>
>FWIW, the Windows host is running a Comodo firewall. Would I need to 
>allow connection to a given TCP/UDP port?

-M messaging is an SMB1-only thing I believe. Is the
Windows7 box running an SMB1 server ?