SMTP error in Thunderbird

English Network/Internet
1

Good day all,

Strangest thing happened,
Its not possible to send mail with Thunderbird in LEAP 15.2,

While doing so the SMTP server generates an error,
different settings for the SMTP server are no solutions,

even after reinstall of LEAP the problem persists,

Error;
There is a fault sending the e-mail: fault with outgoing (SMTP-)server. The server reply: Bad HELO: localhost.localdomain does not exist - Please see RFC 2821
section 4.1.1.1.

I have no clue how to proceed,
windows 10 Thunderbird with the same settings is able to send mail.

Could it be an LEAP 15.2 problem?

Are there more people with the same problem?

Regards Hendrik.

2

Did you try to actually google it?

Thunderbird sends FQDN associated with outgoing interface as part of HELO. Somehow this address is associated with localhost.localdomain. Some mail serves do not like it. Normally if there is no FQDN TB should just send IP literal.

localhost.localdomain for non-loopback IP does not sound right. Or is your SMTP server on the same host?

3

A general comment about running an SMTP server on your local machine…
Once upon a time you could do this, and generally speaking is possible only if you’re running your own mailserver so can create a special security configuration to accept SMTP connections on your own behalf.
All Production mailservers today will block mail from ad hoc SMTP mailservers by IP address as a common anti-SPAM measure.

Perhaps the only time you should point your Thunderbird SMTP to localhost.localdomain is when

  1. You have a name resolution pointing localhost.localdomain to an IP address where a SMTP relay like Postfix is running.
  2. You are running a SMTP relay bound to that IP address.
  3. Since a SMTP service running on your local machine’s IP address is almost certainly not a registered SMTP address, you will have to configure the SMTP service on your local machine to relay to a registered SMTP address, commonly provided by your ISP or a mail service on the Internet. That way when your message is ultimately delivered to the recipient’s mail server, the message will be stamped with the Registered SMTP Mailserver to satisfy anti-spam requirements, not your machine.

Note there are acceptable variations on the above, for instance running an outbound anti-spam filter, SMTP re-routing, proxying for other filtering, etc.

Note that technically there is nothing wrong mapping localhost.localdomain to a remote location although it’s common convention to point to 127.0.0.x /24.

HTH,
TSU

4

Well, as a lot speculation has already happend: Do you run a SMTP server on your local machine or do you try to connect to some remote server?
Also: Setting a propper hostname may could also fix it.