What else would you expect to happen when you "remove" an account? It will be removed from Thunderbird, surely? Along with its folders, surely?

Were they IMAP or POP?

If POP, the related folders are still in your profile. Personally, in this situation, I would browse prefs.js to discover the account's mailstore folder names, and then move those folders into Local Folders. You do all this in your file manager e.g. Windows Explorer.

If IMAP, I would, if possible, reinstate the account(s) in Thunderbird since the messages are stored on the server, and then move the messages I wanted to keep into another account, either a working account or Local Folders. You could try the same trick as with a POP-connected account, i.e. move the mailstore folders, but I wouldn't have 100% confidence that you'd recover all of the content of all of the messages. The locally stored folders in an MAP-connected account are a cache and are not guaranteed to be a full and complete copy of the message store.

How to open the prefs.js file? When I double click on it, I am getting error message (see file uploaded).

Shift+right-click, select "open with" and then use Notepad.

That is too technical! Could locate the email ids I removed. What next?

Which bit is "too technical"? Using Notepad, or editing a prefs.js file?

If you are sure which folders represent the account, just move them into Local Folders.

Were they POP or IMAP?

Of course, editing the prefs.js file. Both were POP accounts. Sorry to bother you, but I am a novice. Which line in the file represents a folder? How to move them local folders?

It can be a bit convoluted. You can also do this searching in the config editor, under Tools|Options|Advanced|General.

I'd do a search for the email address. This should give you a connection to an account mail identity.

user_pref("mail.identity.id4.useremail", "xxx@gmail.com");

(Be careful; if you have set this account up more than once, you may find multiple occurrences of this address. Usually you want the one with the most recent date.)

That will let you find the associated account number.

user_pref("mail.account.account19.identities", "id4");

That account number will give you a connection to a server id:

user_pref("mail.account.account19.server", "server10");

And that server id will take you to a folder pathname.

user_pref("mail.server.server10.directory", "C:\\Users\\xxx\\AppData\\Roaming\\Thunderbird\\Profiles\\my_profile\\ImapMail\\imap.gmail.com");

In each case, you do a search for the magic number you have just found to get to the next one.

This tells me that the message store for this (IMAP) account is in

C:\Users\xxx\AppData\Roaming\Thunderbird\Profiles\my_profile\ImapMail\imap.gmail.com

POP accounts and Local Folders will be stored under

C:\Users\xxx\AppData\Roaming\Thunderbird\Profiles\my_profile\Mail\…

So you move what you have found into Local Folders:

C:\Users\xxx\AppData\Roaming\Thunderbird\Profiles\my_profile\Mail\Local Folders\imap.gmail.com

Could get the following on searching my email id in the file - user_pref("gmcont.anand@dkca.in.aburi", "moz-abmdbdirectory://abook-1.mab"); user_pref("gmcont.anand@dkca.in.moz-abmdbdirectory://abook-1.mab/MailList15.groupId", "http://www.google.com/m8/feeds/groups/anand%40dkca.in/base/6"); user_pref("gmcont.anand@dkca.in.moz-abmdbdirectory://abook-1.mab/MailList16.groupId", "http://www.google.com/m8/feeds/groups/anand%40dkca.in/base/2e612c060d2496f7"); user_pref("gmcont.anand@dkca.in.moz-abmdbdirectory://abook-1.mab/MailList17.groupId", "http://www.google.com/m8/feeds/groups/anand%40dkca.in/base/71535c020b092490"); user_pref("gmcont.anand@dkca.in.moz-abmdbdirectory://abook-1.mab/MailList18.groupId", "http://www.google.com/m8/feeds/groups/anand%40dkca.in/base/7b16c5858ad1574a"); user_pref("gmcont.anand@dkca.in.serialNo", 0);

Nothing against mail.identity.idx

What does that mean?