From: nospam@needed.invalid   
      
   On Thu, 3/5/2026 3:32 AM, ...w¡ñ§±¤ñ wrote:   
   > On 3/4/2026 4:18 PM, War Preparations wrote:   
   >> Can emails be sent within a network without using the internet?   
   >>   
   >> For example, governments might block the internet during a war to   
   >> prevent hackers from spying. If you have your own mail server and only   
   >> want to communicate with 255 people, would this be possible? Armies   
   >> around the world would need a way to communicate with their commanders.   
   >>   
   >> Just a thought.   
   >>   
   >>   
   >>   
   >>   
   >   
   > A mail server can operate on a local network (LAN) without internet by using   
   internal SMTP/IMAP/POP3 services.   
   >   
   > Email clients (Outlook, Thunderbird) need(required) to be configured to   
   point to the local server's IP address for both incoming(POP/IMAP) and   
   outgoing(SMTP).   
   >   
   > Email server software is necessary.   
   >  - open source(free) may be available   
   >  => when looking for opensource, ensure that the company and development is   
   current. i.e. open source(especially free) may be available, but no longer   
   developed, supported, or updated.   
   >   
   >   
      
   I use hmailserver in a VM, to test email clients.   
      
   The hardest part of that, is preparing a certificate for   
   it to use. The unencrypted options are really disabled   
   and not usable, leaving only encryption-in-flight and   
   the email clients expect a valid certificate for that.   
   And generally, you cannot get a quality certificate   
   for a mail.local domain . Clients can insist on valid   
   reverse DNS, and reverse DNS that does not involve   
   the HOSTS file too.   
      
   It's not trivial removing all the handcuffs on this stuff.   
      
   hmailserver is also no longer supported. It was supported   
   when I first installed it, but it has gone out of support   
   since.   
      
      Paul   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)