Reinstalling Thunderbird has no effect, nor does removing authentication.

Are you using version 128? If so, try reverting to 115 and see if that works. That error message I've never seen before. You can see version number at help>about. Ver 115 is available at https://ftp.mozilla.org/pub/thunderbird/releases/115.13.0/win64/en-US/ (assuming English and USA). If that's not right, use this link for other options: https://ftp.mozilla.org/pub/thunderbird/releases/115.13.0/ I would install over the current installation, There may be a compatibilities.ini file in the profile to remove after the update. Let me know how it goes.

Hello there

The version of your Thunderbird Software program can be found by going to your menu and clicking troubleshooting mode information, clicking on it and a tab will open, this information will display you about your setup. Application basis (refer to the number beside Version) data includes the number of which Thunderbird Software is used on your running PC.

Greetings Firefox volunteer

Hello there

The problems lie with the login of the server it had or has seemingly an unsecured pop3 moment and is not going to accept Spam or the like and tried to increase the security levels so as to continue where it fails. It is sometimes recommended that the tls or starttls do not afford encryption at all, but this is more discouraged for users.

Upgrades to the Stls or Tls are failing. Your encryption or security refuses to protect or honor your Tls creation, use, or connection.

And it is a quit old error. Greetings Firefox volunteer

David> Reverting to version 115 has helped quite a lot, thank you. Once I'd made that change, roughly 50 of the 80 or so mails on my server downloaded successfully to Thunderbird. But after downloading those 50, I'm now getting the following message whenever I try to download more - "Unable to write the email to the mailbox. Make sure the file system allows you write privileges, and you have enough disk space to copy the mailbox." There's plenty of space on my disk, so I don't know if this means that my inbox folder has become corrupted. Any suggestions on how to proceed from here?

I have no idea. Others have posted this problem, so a solution may exist. My approach would be to - click help>troubleshootinginformation - scroll down to 'profile folder' and click 'open profile' - exit thunderbird - you are now in profile. click Mail folder, then POP account folder and then COPY the inbox and inbox.msf to somewhere else for safekeeping - restart thunderbird - highlight the inbox, rightclick, select properties and then repair and see if that works.

That doesn't seem to have done anything, apart from partially download one outstanding message (just the first line of text and nothing else).

I have a backup of the Thunderbird profile that I took after the upgrade to 128, as well as a backup of my mail folder taken around the same time - is there anything I can do with those?

yes, there are two ways: - one is to exit thunderbird - if you backed up the thunderbird folder, you can copy on top of the current thunderbird folder at c:\users\<appdata.\roaming\thunderbird and restart thunderbird. - two is to use tools>import>importfromathunderbirdinstalation and then select the profile

It looks like restoring the Thunderbird folder has fixed the problem. During the download of mails, I got the 'Unable to write the email to the mailbox' message again, halting at exactly the same mail - the one that just came through as one line of text. I deleted that mail from the server and the rest downloaded just fine, so I'm not quite sure what that mail was doing.

So at the moment, I have a working email system, but using 115 rather than 128. Does this mean I'll have to stay on the old version from now on?

Hello there

Yes, you can use all versions of Thunderbird. Since the bad mail folder is vanished. It seems to be Oke.

Can I ask what kind of computer pc is there ?

So it was a folder on our mail server after deleting it was the topic solved , maybe something had temporarily penetrated to there where hackers could have been waiting.

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Hello there

The information can also be wrong or viewed, it is more than above 30 degrees here, fortunately everything has been solved, I grab a bowl of water.

Greetings Firefox volunteer

No, but do update settings>general to STOP autodownloading for now. 128 is a huge release and is having the normal birthing pains, but it will be there. I am at 128.1 and all is well. And your update may have been intercepted by an antivirus. If you're open to try, you can do a full backup first and then upgrade while you watch. exit thunderbird and copy c:\users\<yourid>\appdata\roaming\thunderbird to anywhere else. and then upgrade.

Hello there

Yes, trust is back with the users with the arrival of Thunderbird 128.0, too bad about this notification that that one person can't use this.

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