Doesn't bear any relation at all to what I see on my new computer. Can I transfer the old program and expect it to work ?

Tools/Account Settings, is the method via the 'Menu Bar' which you may not have enabled.

Try via the 'Mail Toolbar': 'Menu icon' > 'Options' > 'Account Settings' click the Account Actions button at the bottom left, then Add Mail Account.

OR 'Menu icon' > 'New Messages' > 'Existing Mail Account'

I am obviously too stupid to use this advanced software. I can't see any of the features that I should.

At the risk of my repeating myself, I downloaded the new version thunderbird because I thought it was obligatory for the Windows 10 operating system, which I have been forced to upgrade to (from Windows xp).

Do I need the new version ?

If I do then all is lost, because I simply do not see anything that corresponds to what you very helpful gentlemen have described.

There does seem to be a relatively cheap alternartive which is simpler, supported, and "feature poor". Perhaps I should go for it.

I think a screenshot of your Thunderbird and its main window might be useful. Then we can tell what you can and can not see, and advise you what to do next.

https://support.mozilla.org/en-US/kb/how-do-i-create-screenshot-my-problem

I'v got a screen shot, and I can see that there is a thing with the legend "menu bar" on it, which was ticked. It would help me if you would send a screenshot of a cuRrent thunderbird screen, as you see it. Then I could could compare. I can't send you a screenshot, other than by emailing it to support@mozilla.org which a I don't suppose will work, but I will try it. This is because my windows 10 computer doesn't have a proper email client.

You can post your screen shot to this forum.

My Thunderbird is rather heavily customised. I have the Menu Bar and my most often used buttons on the main toolbar. I don't use the smaller toolbar inside the lower message pane. I do have the new Application Menu button but I have it in an unconventional (but to me, logical) position.

You can right-click an existing account and then choose Settings, which will open the Account Settings window. In this window, the button at the bottom of the left hand pane will let you add an account.

It's easier to work by you showing us what you have, so we can tell you what to do. If someone else posts their screenshot we'll still be struggling to match up what you see with what they post.

If you really don't want to post your screenshot in public, you could send it to me personally at xenos at gmx dot co dot uk. I'm sure you can send email via your browser.

Hmm. if you spent a couple of minutes exploring your menus and views you'd find this, shown below.

This is Thunderbird in Safe Mode, so it is unadorned, unchanged from what you initiailly get when you download it.

I don't often see this "Accounts Central" page, because I have it replaced by something more informative and useful.

from https://support.mozilla.org/en-US/questions/1166812 which is now locked as a duplicate topic.

I am making slow progess with this query, and cannot see the answers already provided. I've found out how to get a menu bar. I've found account settings. But I can't see the option to add a new account. Why not ? Nor can I see answers to my previous query.

Yet another route in, given that you say you have restored the traditional menu: File|New|Existing Mail Account….