Hi Renee.

Rght click on the folder name, select "Properties", then "Repair Folder", and report the results.

Well, unfortunately I tried the Repair Folder option, and now two years of saved emails have completely disappeared, from 9/2023-9/2025!!!! Does Mozilla/Thunderbird look at these questions because now I have NOTHING! No subject line and information I saved for a reason. Is there any hope to recover these messages?

Hi Renee,

I am sorry to hear that. I do not have an explanation. Repairing folders is a common step to take in these situations and often effective. It does not delete messages.

Are your messages gone or are they present but blank?

Do you have a back-up copy of your data?

Someone else may be able to help more than I can. I will inquire.

Hello again.

What version of Thunderbird are you using?

Recommendations from a senior support person:

Back up your Thunderbird profile now. An easy way to do that is to use the "Tools" menu > "Export..." and put save the export file to an external drive or save it to your internal drive, then copy it to an external drive. If your profile folder is larger than two gigabytes, we should use a different method. To see how large the profile folder is:

1. "Help" menu > "Troubleshooting info"
2. Find the row in the table for "Profile folder" and click on "Show in [varies by system]" next to it.

You will then see the profile folder in the file system. Do you see the size of the folder? If not, right click on the folder and select "Get Info".

If you have a back-up copy for your data from before this recent turn of events, let's restore your data from it. Do you have such a back-up?

I am still trying to learn more about causes of this problem.

Your messages may still exist but Thunderbird is not showing them to you. Let's find out.

1. "Help" menu > "Troubleshooting info"
2. Find the row in the table for "Profile folder" and click on "Show in [varies by system]" next to it.
3. Open that folder.

If you have a POP account, as you think you do, the message folders are inside the "Mail" folder. Open that folder. Do you see the folders that held your missing/blank messages? What is their size?

If you have an IMAP account, the message folders are inside the ImapMail folder. Open that folder. Do you see the folders that held your missing/blank messages? What is their size?

If messages are missing or blank from your local folders, look in the "Mail" folder for the "Local Folders" folder. Open that folder. Do you see the folders that held your missing/blank messages? What is their size?

Let's make sure we know what kind of account you have.

1. Right click on the name of the account in the folder pane.
2. Select "Settings".
3. Click on "Server Settings" in the left pane.
4. The server type is identified right below "Server Settings" in the right pane. What is the server type?

Hello,

- I am running Thunderbird on an iMac. - The messages are GONE. I used to have a few thousand in my inbox and now have about 500. - When I check the Server Settings, it shows POP mail server - I am running Thunderbid 140.0.0esr (Eclipse?) - The size of the Profile Folder is 5.68 GB - When I look at the Mail folder in the Troubleshooting mode, it shows an Inbox with 158.8 and and inbox of 2.73MB.

Thanks for the information. Sorry, I realized later that you had already said that you use a Mac.

Do you have two inboxes in your Mail foder or is one of them somewhere else? Where?

158.8 what? MB? If so, there may still be a few thousand messages on disk that are not appearing in Thunderbird. That would be good news.

A profile of size 5.68 GB is holding many messages. Which folders are experiencing this problem? Just the inbox or others too?

POP accounts have an option to leave messages on the server after they have been downloaded to a client such as Thunderbird. Have you set that option? When you log into webmail on the website of your e-mail service provider, are the missing messages there?

Another user has reported losing messages from the inbox. Like you, they were using version 140 on a Macintosh.

https://bugzilla.mozilla.org/show_bug.cgi?id=1978465

You did not answer my question about back-ups. Do you have any?

Renee, if you have a back-up copy of your files, people here can help you restore them. If there are 158.8 MB of messages in your inbox, your missing messages may be recoverable there. Again, people here can help. Please let us know if you care to try either of these approaches.

I am still trying to determine if my Thunderbird email is backed up to an external hard drive.

In the Troubleshooting Information => Profile Folders => Mail = > My Local Folders => Inbox Folder - that folder shows 1.6GB.

How could I go about retrieving the (without knowing if they've been backed up externally.)?

My online server keeps emails for so long then they can intermittently disappear. I have not figured out why, which is one of the reasons I have kept Thunderbird so long.

Thank you.

Good morning, Renee,

A size of 1.6 GB indicates many thousands of messages. Using my own folders as a reference, I calculate 25,000 - 35,000 messages. (I don't store attachments with messages. If you do, you will have fewer messages in 1.6 GB than I do.) That's good news. Let us hope now that they can be recovered.

Before doing anything else, I would learn with certainty whether or not a recent back-up copy of my profile exists.

I would also make a back-up copy of my profile. The easiest way to do that on a Mac is to drag the profile folder to an external drive. If you do not have an external drive, you should get one, at least a large-capacity USB "thumb" drive that can hold a copy of all your important documents and data, including your Thunderbird profile. (You should also use Time Machine to back up your whole hard drive regularly, except for some files that do not need to be backed up, which you can exclude.)

When you are ready to attempt to recover the messages in that inbox file, here are the steps that I would take:

1. Copy that inbox file from the Thunderbird profile to the desktop. The easiest way to do that on a Mac is to option-drag the file from the profile folder to the desktop. You know now (see above) how to get to your profile folder, and you seem to know how to drill down in it to the 1.6 GB file. Make sure that you hold the option key down before you click and drag and keep it held down until the you have released the file on the desktop.
2. Rename the file on the desktop to differentiate it from your inbox. I might name it, full of hope, "Recovered inbox".
3. Install the excellent Thunderbird add-on ImportExportToolsNG. "Tools" (menu) > "Add-ons and Themes", search for "ImportExportToolsNG", click the "Add to Thunderbird" button when you find it.
4. Return to the main Thunderbird window that shows the folder pane and e-mail messages.
5. "View" (menu) > Toolbars. Make sure that "Status Bar" is checked. If it is not, select it.
6. Right click on "Local Folders" in the folder pane. You should see a drop-down menu. At the bottom of the menu should be an option for "importExportToolsNG". Select it. The menu will then cascade to show more options. At the next level, select "Import mbox files". At the next level, select "Individual mbox files".
7. You should then see a file selection window. In that window, navigate to your desktop and select the inbox file that you renamed.
8. If ImportExportToolsNG is able to read the file, it will need a few minutes, depending on the speed of your computer, to import the messages. Since you ensured that "Status Bar" is enabled, you can monitor the progress at the bottom of Thunderbird's main window.
9. In the best case, ImportExportToolsNG will import 25,000 - 35,000 messages and you will be on your way to making everything right again. I don't know how much hope we should have because I don't know what the problem is with your inbox. I am hoping for the best.

Please stop and ask questions if you have difficulty with anything.

Oh, we also must still worry about what caused this problem because it could occur again. I'm sorry that I don't have a recommendation. I assume that your version 140 is "140esr". Is that right? You could switch to the monthly release channel. It's possible that it will not have whatever caused this problem. But that is only a hope. It's also possible that it has the same problem or even new problems. You can learn about release channels here: https://support.mozilla.org/en-US/kb/choosing-thunderbird-release-channel

If you want to make a change, you may want to ask for guidance here before starting. Please don't hesitate.

One other thought: 1.6 GB is rather large for a single folder. Thunderbird should be able to handle it, but I can imagine more problems with a folder of that size than with smaller folders. I am only wondering. I do not know of specific problems that can occur with large folders. In your place, I might reduce the size by deleting old or unneeded messages and filing messages in other folders.

Please let us know how it goes. (I dislike support people using the first-person plural to refer to themselves. When I use it, I am referring to a group of about ten knowledgeable people who provide much good support on this forum.) If this operation works, we'll need to figure out what to do with your active inbox and all the imported messages.

Just jumping in with some suggestions (that may have already been pursued): - please post a screenshot of your profile, primarily the folder of the POP account. That would be the Mail\<POPaccount> folder. If there are multiple accounts, a screenshot of each will help. The intent here is to see what files are responsible for the 1.6G size. - I also suggest deleting the global-messages-db.sqlite file, and let Thundebird rebuild it (Do that when thunderbird is not running) I suggest this because a search for messages goes through the global index, which will still show messages as being present when, in truth, they are no longer there. Rebuilding the global index resolves that perception of messages that aren't there. - I believe Rick has already mentioned this: POP accounts need periodic backups because the only copy is on the PC.

Thanks, David!

How is it going, Renee?