1. For those e-mails, the attachments have been stripped from the e-mail for some reason. This could have been done by an add-on for Thunderbird, or by your e-mail server.

I know of one Thunderbird add-on which is supposed to automatically detach attachments, but actually strips them and leaves exactly what you see. That add-on is called FiltaQuilla, and it doesn't work very well. If you have that add-on, either disable it's ability to auto-save attachments, or remove the add-on entirely. Or it could be another Thunderbird add-on you are using that is doing this.

Since you are using IMAP, It is possible that your e-mail server has stripped the attachments for some reason. Maybe to save space.

2. If the folder that has those older messages really has enabled "Select this folder for offline use", then it shouldn't say it is downloading the message. It would already be on your computer, thus no downloading.

Try some cleanup in Thunderbird:

1. Go through your Junk/Spam folder. Check to make sure no good e-mails are there, then empty the folder.

2. Thunderbird Menu: File: Empty Trash

3. Thunderbird Menu: File: Compact Folders

Do this for each "account" in Thunderbird, including Local Folders.

Quit Thunderbird, then start it again.

If it has been awhile, reboot the computer!

Bruce,

I don't have FiltaQuilla, and further I disabled all add-ons from Thunderbird, but the problem was the same. When I started compacting the folders, it showed that messages started downloading for every folder I compacted. But attachments showed, but with size unknown and will not open when clicked.

Regards,

LS

lsingh said

When I started compacting the folders, it showed that messages started downloading for every folder I compacted. But attachments showed, but with size unknown and will not open when clicked.

I believe that the server stripped the attachments at some point. Possibly to save space because your e-mail took up too much space. You need to communicate with whoever your e-mail provider is, and ask them about this.

When you compacted the folders in Thunderbird, it then re-synchronized the old messages with the server, replacing the good e-mails on your computer with the ones on the server that had the stripped attachments.

To avoid this in the future, communicate with your e-mail provider and/or save your e-mail permanently in Thunderbird in "Local Folders".

Bruce,

Gmail and hotmail are the service providers for both my email ID's and it is happening to both of them. I think it is something to do with Thunderbird? I am not sure. Thanks.

Regards,

LS

To rule out the possibility that Thunderbird is causing this, you should create and use a new Thunderbird Profile. Also make sure that Thunderbird is up-to-date.

Keep in mind, though, that you are going to be able to recover those attachments that have already been stripped from the e-mails. This is to stop attachments from being stripped in the future.

1. Copy (not move), all your e-mails to "Local Folders" in Thunderbird. This will ensure that you have them saved to your computer, and are not relying solely on them being on the e-mail servers.

2. Delete any Junk that is in the Junk folder under "Local Folders".

3. Select "Local Folders", or any folder under it, and then compact the folders Thunderbird Menu: File: Compact Folders

4. Check to make sure that Thunderbird is up-to-date: Thunderbird Menu: Help: About Thunderbird. The current version is 45.7.0. An update will download now if Thunderbird is not up-to-date. Let it download & install. Then restart Thunderbird. Repeat if necessary until the Thunderbird version is 45.7.0.

5. Follow these instructions: Create a clean new profile in Thunderbird and import your stuff from the old profile

What anti virus are you using? It is fairly common for anti virus program to simply mess up attachments to email when they scan them especially in the case of IMAP

Yes, what Matt said.

Thanks Bruce, Matt. I am using Norton 360.

Norton has a long history of messing up all sorts of things with e-mail. Other antivirus programs cause fewer problems with e-mail.

I don't know if Norton is the cause of the stripped e-mail attachments. You can check the various settings in Norton to see if it has an option that does this.

The only way to know for sure if Norton is doing this is to disable its e-mail scanning module/functions and set up an exception in Norton for your Thunderbird Profile folder. This will mean that Norton will never scan your e-mails, which is not really safe.

Aside: It is recommended that e-mail scanning be disabled in antivirus programs, because antivirus programs already automatically scans everything when it is accessed. So e-mail scanning is an unnecessary duplication, and that e-mail scanning itself can cause problems.

If you are using IMAP mail. Disable Norton's mail scanner permanently. It does not scan IMAP mail accounts, nor does it scan mail on connections using SSL/TLS. That is probably 99% of mail providers these days.

Thanks. Also, when I click on some messages, they are shown as downloading. I have checked the messages to be stored on this computer, but it still seems that Thunderbird is downloading the messages. Any advice on this please?

how much mail do you have to download? and how much time has Thunderbird been running and with what bandwidth and contention issues to achieve that. Massage headers will come first, but depending on how much mail you have a full download could take days. especially if you using a provider that limits available bandwidth on a daily basis lie Google do. With Norton, you might be able to double of triple the time taken over no anti virus. but it will increase (slow your system really) increase by at least 30%