unable to connect to local network via openssl or telnet

[Jerry]

FreeBSD 11.4-RELEASE-p4
OpenSSL 1.1.1h 22 SEPT 2020

I recently had to do a fresh installation of FreeBSD on a new HD, do to
the fact that the old HD died. I cannot install anything newer than
11.x due to a bug
<https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=237666>.

After the new installation, I attempted to check Postfix and Dovecot
via 'telnet' and OpenSSL. Now when I attempt to use telnet to access
either one from a machine on the network, I receive an error message:

telnet domain.net 25
Trying XXX.XXX.XXX.XXX...
telnet: connect to address XXX.XXX.XXX.XXX: Connection refused
telnet: Unable to connect to remote host

Now, if I use the full computer name, everything works as expected.

The same problem happens with OpenSSL

openssl s_client -connect domain.net:587 -starttls smtp
34387091456:error:0200203D:system library:connect:Connection refused:crypto/bio/b_sock2.c:110:
34387091456:error:2008A067:BIO routines:BIO_connect:connect error:crypto/bio/b_sock2.c:111:
connect:errno=61

If I use the full computer name, it works.

If I try either command from a PC not connected to the same network,
using either name, everything works as expected. I didn't have this
problem before I did the reinstall. I don't think it is a firewall
problem because I have tried with the firewall disconnected.

This is not the behavior I experienced before this reinstall. I figure
I am doing something dumb, but I cannot figure out what, and I don't
have a lot of time to play around with it; I am getting really busy at
work now.

I am open to suggestions.

-- 
Jerry