Unable to add account to Thunderbird.

[#1]

I will review this later. I’ve probably not clicked the difference between doing this in powershell vs cmd.

[#2]

So I emailed Spamhaus as it was blocked on there and voila they removed the block and it's working again (for) now!

[#3]

"NB not sure if curl is installed by default in windows ?"

I've never (knowingly) installed it. And I've been oblivious to its presence.

Microsoft Windows [Version 10.0.19045.5487]
(c) Microsoft Corporation. All rights reserved.

C:\Users\user2>curl
curl: try 'curl --help' for more information

C:\Users\user2>curl --help
Usage: curl [options...] <url>
-d, --data <data> HTTP POST data
-f, --fail Fail fast with no output on HTTP errors
-h, --help <category> Get help for commands
-i, --include Include response headers in output
-o, --output <file> Write to file instead of stdout
-O, --remote-name Write output to file named as remote file
-s, --silent Silent mode
-T, --upload-file <file> Transfer local FILE to destination
-u, --user <user:password> Server user and password
-A, --user-agent <name> Send User-Agent <name> to server
-v, --verbose Make the operation more talkative
-V, --version Show version number and quit

This is not the full help; this menu is split into categories.
Use "--help category" to get an overview of all categories, which are:
auth, connection, curl, deprecated, dns, file, ftp, global, http, imap, ldap, output, pop3, post, proxy, scp, sftp,
smtp, ssh, telnet, tftp, timeout, tls, upload, verbose.
For all options use the manual or "--help all".

C:\Users\user2>curl -V
curl 8.9.1 (Windows) libcurl/8.9.1 Schannel zlib/1.3 WinIDN
Release-Date: 2024-07-31
Protocols: dict file ftp ftps http https imap imaps ipfs ipns mqtt pop3 pop3s smb smbs smtp smtps telnet tftp
Features: alt-svc AsynchDNS HSTS HTTPS-proxy IDN IPv6 Kerberos Largefile libz NTLM SPNEGO SSL SSPI threadsafe Unicode UnixSockets

[#4]

Thx. The 'sport' of curling

[#5]

@Townman 

To conclude my testing for Free Online for STARTTLS

curl -v smtp://relay.free-online.net:587 -u <accountname>:<password> -ssl

curl -v smtp://relay.free-online.net:587 -u <accountname>+<mailboxname>:<password> -ssl

curl -v smtp://relay.free-online.net:587 -u <accountname>@<accountname>.free-online.co.uk<password> -ssl

curl -v smtp://relay.free-online.net:587 -u <mailboxname>@<accountname>.free-online.co.uk:<password> -ssl

Using smtps defaults to using port 465

curl -v smtps://relay.free-online.net -u <accountname>:<password>

These commands could be used as an alternative to using telnet.

I've also looked at openSSL in linux which provides similar results

[#6]

I've also looked at openSSL in linux which provides similar results

On linux, of course, you can always use swaks

(Swiss Army Knife SMTP) is a command-line tool written in Perl for testing SMTP setups

https://github.com/jetmore/swaks

[#7]

@Scotty12 

Thank you for asking questions which in the attempt to answer has exposed a simpler way of running SMTP diagnostic testing.

@MisterW and @Dan_the_Van 

Thank you for the 'build' on the idea.

I have now obtained the same results ... a little shocked to see the same command behave so differently in PowerShell to a CMD prompt.  I was not expecting such an apparently powerful command to be a CMD function.

Now need to add revising the SMTP test standard response text to my work stack!!