I'm afraid that Thunderbird is a client and not a server. You'll need to look for something else.

Zenos said

I'm afraid that Thunderbird is a client and not a server. You'll need to look for something else.

Zenos, thank you for your very prompt reply confirming that I cannot use Thunderbird as a local email server. Do you have any suggestions for a Windows based Local Email Server which Thunderbird Clients works well with?

I'm afraid not. I've written programs that use email client functionality and that was using drag-and-drop type components that did all the work after a little bit of configuration. All I have read about email servers tells me they are hard to do properly.

I assume you don't want to spend a lot on this. So that leads you to open source solutions. The names I encounter most often are exim, dovecot, postfix, qmail and sendmail.

There is a list and comparisons table here:

https://en.wikipedia.org/wiki/Comparison_of_mail_servers

Those with GPL licences will be free to use. Anything labelled as "proprietary" or has a specific brand name in the licence column will probably need to be paid for.

I fear none of this will be as easy to use as turnpike. :-(

Zenos, many thanks for your advice on Local Email Servers it has given me a good starting point. Re the cost of a replacement system, I have really no objections to purchasing appropriate software, so long as it is being supported. We are only a small home office with two/three users. There is still an option that we need to investigate here, which is using the Turnpike Connect (Email Server) with Thunderbird as the Email Clients.

MarkRowe: So is the only reason you want to use an email server purely for backup purposes being made easier?

I'm not aware of the scale of your workload, but this is just an idea to consider as it may work for you....... Thunderbird can be downloaded to each computer and a profile can be set up on each computer with imap mail accounts. If everyone is using IMAP mail accounts, then all emails are on the server of ISP and your colleagues on various computers can use Thunderbird to see a remote view of emails on server.

Assuming some people have access to some email addresses/mail accounts, but not necessarilly all of them. You could set up one designated computer with all email addresses as mail accounts. Folders are synchronised and allowed to store emails locally on that computer.

Example: Once a day at close of day, a designated person logs on to User Account, opens Thunderbird and gets the folders synchronised for offline use to download copies of all emails onto that computer. Then in offline mode, create a backup of the profile containing all mail accounts to eg: external hardrive. Backup is as simple as copy pasting a Profile name folder or if only IMAP mail accounts info required then the 'IMAPMAIL' folder containing the mail accounts.

This does not stop backups being made of other profiles on other computers.

Toad-Hall, thank you for your suggestion. Backing Up is just one of the items we would like to retain, but equally important is to have the ability for different users to be able to see and reply to emails, with the reply being kept on what would be the Local Email Server and not on the individual's own computer. Equally, at the moment we can, go to any of our local computers, and logon to our individual email profiles (hot desking?) and carry on working. Things like centralised Address Book, ability to see customer emails and our replies, encrypted email database, i.e. all the things Turnpike currently provides us. It is looking more like that we will have to tested running Turnpike Connect behind Stunnel, with Thunderbird as our Email Clients.