If the messages are on the server, just subscribe to their folders by right clicking on the account name in the folder pane, selecting "Subscribe", and checking the folders that you want to see in Thunderbird.

If the messages are not on the server, where are they?

If the messages are on the server, they are not really "transferred" to Thunderbird. They appear in Thunderbird only because they are still on the server. Delete them from the server, and they will be gone from Thunderbird too. If you really want to transfer messages, create local folders and move your messages to them.

I need the email in the folders on the server so I need them to exist in Thunderbird. I understand how to make new folders but how do I move the messages to the new folders?

Not clear to me yet.  :(

So the messages that you want to “transfer” are on the server now?

Do those messages appear in Thunderbird now? If not, have you tried to subscribe to them?

Do you want the messages to end up 1) on the server and in Thunderbird or 2) only in Thunderbird?

Then let us decide the best way to “transfer” them.

I need the messages to end up on Thunderbird as I am dropping the ISP that hosts them now

Again: Do those messages appear in Thunderbird now? If not, have you tried to subscribe to them?

Once you get the messages showing up in IMAP folders in Thunderbird, if they are not already  … 

You should back up your profile folder before continuing: https://support.mozilla.org/en-US/kb/thunderbird-export

How you move messages depends on how many you have. If you have tens of thousands, then, I'm told, copying them from IMAP folders to local folders could be unreliable. So you want to see if your e-mail service provider offers a way to download your messages directly from the server without having to use another e-mail client. For example, Google has a "take out" process and Yahoo has something similar. That kind of process would also be better if you have many tens of folders because using the process described below would be tedious, time-consuming, and perhaps error-prone.

If you have relatively few messages and folders, you should copy (not move) the messages from IMAP folders to local folders.

1. Create the local folders that you want. Right click on "local folders" in the message pane and select "new folder". You said that you already know how to do that. Good.
2. Select all the messages in a folder that you want to transfer. Control-a (command-a on a Mac) selects all messages in a folder if that folder has the focus.
3. Right click on the selected messages, select "copy to" and the destination folder.
4. Monitor the copying until you are confident that all the messages have been copied.
5. Repeat for each IMAP folder.
6. Check that the quantity of messages is the same in every pair of source and destination folders.
7. Make another back-up copy of your profile folder.

You can now delete the IMAP folders.

Before you leave your ISP, of course, you'll want to preserve all your messages in the special IMAP folders (inbox, sent, etc.) too. Same process.

Trying this again

Not clear to me yet.  :(

So the messages that you want to “transfer” are on the server now? 'YES in several folders'

Do those messages appear in Thunderbird now? If not, have you tried to subscribe to them? No, I don't know how to subscribe Do you want the messages to end up 1) on the server and in Thunderbird or 2) only in Thunderbird? 2

Then let us decide the best way to “transfer” them.

So the messages that you want to “transfer” are on the server now? 'YES in several folders' Do those messages appear in Thunderbird now? If not, have you tried to subscribe to them? No, I don't know how to subscribe Do you want the messages to end up 1) on the server and in Thunderbird or 2) only in Thunderbird? 2 Then let us decide the best way to “transfer” them.

OK, thanks for the information.

I told you in my first response how to subscribe to folders:

If the messages are on the server, just subscribe to their folders by right clicking on the account name in the folder pane, selecting "Subscribe", and checking the folders that you want to see in Thunderbird.

Once you see all the folders in Thunderbird that you need to get messages out of, you can use my instructions above to copy their messages to local folders.

Please let me know how it goes and what more you need.

There is no subscribe option when I right click on what I assume is the account name in the folder pane. I assume the folder pane is the list of all the folders I have on my current ISP email server. There is just a list of folders with names that I assigned containing emails I have saved for several years. I have re-created those folders in Thunderbird with the same names but there are no emails in them yet as I don't know how to populate them with your instructions.

There is no subscribe option when I right click on what I assume is the account name in the folder pane. I assume the folder pane is the list of all the folders I have on my current ISP email server. There is just a list of folders with names that I assigned containing emails I have saved for several years. I have re-created those folders in Thunderbird with the same names but there are no emails in them yet as I don't know how to populate them with your instructions.

Would you please post a screen image of your folder pane?

You said that you set up an account and that you are getting mail in it. By default, the account name is the e-mail address of the account. Do you see your e-mail address in the folder pane? Or another name that you gave the account? That is what you should right click on.

If you set up an IMAP account, you should see something like what is in my screen image. And you should see that drop-down menu when you right click on the account name (whatever is in the top row). Do you?

If you set up a POP account, you should see the name of the account but not server folders. And setting up a POP account would have been a mistake because you have folders on the server that you created and that you need access to. So you need an IMAP account in Thunderbird.

as I don't know how to populate them with your instructions.

You cannot follow my instructions for copying messages because Thunderbird is not yet showing you the messages that you want to copy. If something is not clear in the instructions when it is time to use them, please ask for clarification.

Did you create your folders under "Local Folders"?

I believe I have a POP account as it was the option highlighted when I created it

I believe I have a POP account as it was the option highlighted when I created it

That explains why you don't see other server folders or an option to subscribe. Sorry, I should have considered POP at the start.

I'm not aware that the POP option is highlighted in some way when someone sets up an account. I always see both options. Maybe your server supports only POP? That would be unusual. Who is your e-mail service provider?

You will want to switch from POP to IMAP if your service provider supports IMAP. Here are instructions for doing that: https://support.mozilla.org/en-US/kb/switch-pop-imap-account

After you are done with that, we can continue with the rest of the process.

It's good that you created your folders under the local folders account. To check that was one reason why I asked for a screen image.

If you prefer using POP, you could leave that account as it is and investigate downloading messages from the server in another way, as I mentioned above. I believe that IMAP is better for most people.

The ISP is Mediacom and I just checked and their site claim to off IMAP or SMTP doesn't mention POP. What if I just delete the Thunderbird account and start over. When I created the account the POP option was hi-lighted and another option was not apparent to choose but I didn't try to un-select the POP option. My limited understanding of POP and IMAP is that the emails are only kept on the receiving device and not on the server with POP and IMAP keeps them on the server. My only concern is that I don't loose all these email once I stop using Mediacom a my ISP. I will read the instructions for switching from POP to IMAP before doing anything else

I don't use POP and don't know if it is safe to delete the account, so I think it's better to follow the instructions.

You are right about IMAP and POP.

A good explanation of IMAP: https://support.mozilla.org/en-US/kb/imap-synchronization

You can set whether or not messages in a POP inbox stay on the server.

After you have an IMAP account, you can copy messages to your local folders, where they will remain after you close your account with Mediacom.

I did all the steps to convert to IMAP and now I can't connect to the Mediacom Server. Nothing makes any sense, when I open Thunderbird now it shows I have a POP account

What exactly did you do? What happens when you try to connect? Do you get an error message? Would you please provide more information each time that you write?

Did you do all these steps? —

• Disable your POP acocunt.
• Create the IMAP account. Were you successful? Did Thunderbird find the settings? Does your account appear in the folder pane? Are you seeing any server folders in it?
• Transfer your local messages to the server.
• Delete your POP account.

Please post more screen images:

1. The folder pane
2. Click on the three-lined button at the top right of the screen and select "Account settings". Post an image of the next screen.
3. For each account that appears in the left pane on that screen, click on "Server settings" in the left pane and post a screen image of the right pane.

Please don't get discouraged. What you are trying to do is simple: just set up an IMAP account and copy messages. I think that we're struggling a bit because you are using Thunderbird for the first time, right? And it's been hard to know exactly what you are doing and how the results look.

I'm confident that we can do what you want, and I'm eager to see your response to my last message.

Well I thought I had already responded to your last message with the screen shot of the results of the 3 bar icon display

Here is 3 bar icon results

I asked you to provide more information each time that you respond. You did not answer any of my questions. I asked for four screen images. You provided one. I cannot help you without more information.