Thunderbird Community Forum

Over the last week I have been experiencing issues that prevent me from using Thunderbird on my computer. It had been working for a few weeks prior, with emails sending without issue. Without any apparent cause, and with the correct credentials set in my account settings, emails are no longer sending. They continue to be received with no issue, and I can move emails into folders etc.., which I immediately see reflected in Webmail. I get the attached error, every time I try to send an email, no matter which address I am trying to contact. I can log in to my account with the same credentials on different software on the same computer, and I have no issues with sending emails from that software, so I can't see how this would be an issue with my computer. I have tried removing the account, and adding it again. The credentials are accepted, but the issue persists. The email also works without any issues via Webmail. I have contacted the hosting company for support, but they have confirmed that this is an issue with Thunderbird. Please can somebody help?

1. Was able to receive emails sent to my address xxxxxx@xxxxxxx.free-online.co.uk, but unable to SEND my replies. Was getting this notification: 'Send message error. Sending of message failed. An error occurred while sending mail. The mail server responded: Unknown sender. Please verify that your email address is correct in your account settings and try again, OK' (see attached). 2. Checked all settings, all correct as used to be before the problem started. 3. At some stage, I tried changing the password in Settings > Privacy & Security > Passwords > Saved passwords > Saved logins to see if that helped. It didn't. 4. I removed the free-online Server from the Saved logins (Provider: smtp://relay.free-online.net, User: xxxxxxx) with the intention of restoring it with a new password - but found I couldn't restore the free-online server. So I decided the best thing to do was to restore the password as it was before and to ask for help here. >>> That line has now been restored.

NB1. Free-online is a sub section of Plusnet. NB2. Last year I received an email from Greenby saying something about maybe taking over from Plusnet and that I would be notified if and when I had to do anything. I have not received any such instructions so left things as they were. Many thanks for your help from a not-very-techy so stressed old lady.

Maybe a red herring: I was in the middle of doing a Documents folder backup when I decided to open Thunderbird for some reason. Got an Unable to Load Profile type of message. And my attempts at a fix seem to just send me further down a rabbit hole. I started out by renaming my profile.ini file, but I really didn't know what the heck I was doing and possibly caused more harm than good. Then I tried to find my profile file/folder itself, using the Thunderbird > Troubleshooting > Profile Folder path and doing an import from inside TBird but that ended up with various problems such as drilling down to the profile folder from within TBird but then when I clicked Select Folder in Thunderbird, that didn't trigger any sort of import.

I also spent a good deal of time trying to find my AppData folder, finally being able to view it (a hidden folder, apparently), and saw several recently-dated profile types of folders, but again, I couldn't manage to "hook up" any of those folder/files from starting inside TBird and selecting Import... I ended up just stuck inside a folder, not triggering any Importing activity.

Finally I found a profile folder (5yed...) at a higher level on my PC than inside that long AppData Roaming Thunderbird path. THIS profile was inside: D:\DOCS\Thunderbird\Profiles

Now THAT folder I managed to get an Import to trigger. But the result was an Error Message telling me to go find my Error Console. Can you please see the attached Error Code display screengrab and tell me there's hope that this was at least the right file but just poor results that I can fix somehow???

The following is my copy/paste of the text I see in the Error Console display that's in my screengrab after trying to import the above 5yed... profile, in case it helps you see it better:

1765349209272 addons.xpi WARN Checking C:\Program Files (x86)\Mozilla Thunderbird\distribution\extensions for addons WebGL context was lost. 2 Troubleshoot.sys.mjs:727:17 Content-Security-Policy: This site (https://www.mozilla.org) has a Report-Only policy without a report-uri directive nor a report-to directive. CSP will not block and cannot report violations of this policy. thunderbird downloadable font: Glyph bbox was incorrect (glyph ids 441 459 695) (font-family: "Open Sans" style:normal weight:700 stretch:100 src index:0) source: https://updates.thunderbird.net/media/fonts/opensans-bold.woff2 downloadable font: Glyph bbox was incorrect (glyph ids 459) (font-family: "Open Sans" style:normal weight:400 stretch:100 src index:0) source: https://updates.thunderbird.net/media/fonts/opensans-regular.woff2 Uncaught (in promise) NS_ERROR_FILE_NOT_FOUND: Component returned failure code: 0x80520012 (NS_ERROR_FILE_NOT_FOUND) [nsIFile.copyTo]

   _recursivelyCopyMsgFolder resource:///modules/ThunderbirdProfileImporter.sys.mjs:652
   _recursivelyCopyMsgFolder resource:///modules/ThunderbirdProfileImporter.sys.mjs:661
   _mergeLocalFolders resource:///modules/ThunderbirdProfileImporter.sys.mjs:634
   _importServersAndAccounts resource:///modules/ThunderbirdProfileImporter.sys.mjs:243

ThunderbirdProfileImporter.sys.mjs:652

Also attached below are also:

• a screengrab of a set of profiles I found, but when I drilled down to them from within TBird's Import selections and clicked Select Folder, as far as I got was an open folder, or something like that.
• Thunderbird's Troubleshooting Info "Profile Folder" path.
• Message telling me to see the Error Console. The message appeared right after I tried importing the profile that's stated in TBird's Troubleshooting Info "Profile Folder" path.

Here's the copy/paste of the Error Console message display after my try at importing the profile that is in the path that TBird's Troubleshooting Info page "Profile Folder" states (maybe it's the same as my 5yed...profile import try's Error Console display, dunno:

1765353636640 addons.xpi WARN Checking C:\Program Files (x86)\Mozilla Thunderbird\distribution\extensions for addons Content-Security-Policy: This site (https://www.mozilla.org) has a Report-Only policy without a report-uri directive nor a report-to directive. CSP will not block and cannot report violations of this policy. thunderbird WebGL context was lost. 2 Troubleshoot.sys.mjs:727:17 downloadable font: Glyph bbox was incorrect (glyph ids 441 459 695) (font-family: "Open Sans" style:normal weight:700 stretch:100 src index:0) source: https://updates.thunderbird.net/media/fonts/opensans-bold.woff2 downloadable font: Glyph bbox was incorrect (glyph ids 459) (font-family: "Open Sans" style:normal weight:400 stretch:100 src index:0) source: https://updates.thunderbird.net/media/fonts/opensans-regular.woff2 Uncaught (in promise) NS_ERROR_FILE_NOT_FOUND: Component returned failure code: 0x80520012 (NS_ERROR_FILE_NOT_FOUND) [nsIFile.copyTo]

   _recursivelyCopyMsgFolder resource:///modules/ThunderbirdProfileImporter.sys.mjs:652
   _recursivelyCopyMsgFolder resource:///modules/ThunderbirdProfileImporter.sys.mjs:661
   _mergeLocalFolders resource:///modules/ThunderbirdProfileImporter.sys.mjs:634
   _importServersAndAccounts resource:///modules/ThunderbirdProfileImporter.sys.mjs:243

ThunderbirdProfileImporter.sys.mjs:652

Thanks for any help in getting through this.

I became a THunderbird user recently to help me transfer e-mails from one system (e-mails sent to my e-mail address being collected by Gmail using POP3) - I have a gmail.com address too which shows all the e-mails in the same Inbox. Google are withdrawing support for Pop3. I am moving to Hostinger which happily collects and displays all my emails on its Webmail service. Thunderbird is a great tool for moving e-mails fro Inbox (and al other folders) from the Gmail to Hostinger. But yesterday it crashed and wouldn't restart = white windows says at the top 'not responding = and Windows Task Manager shows me Thunderbird still seems to be talking to one of my accounts and has 6 other tasks open. I stopped those tasks and closed Task Manager. I have uninstalled and re-installed but it comes back with the same symptoms and same tasks running. How do I stop this and get it back properly again

I have got two e-mail by Thunderbird : d.nadal@orange => OK but danielle.nadal@kohinos.net NO connection Thunderbird said : connection time exceeded'. What to do?

Subject: Persistent SMTP block on specific Outlook account (IMAP functional) ​Problem Description: Systematic failure of outgoing emails via SMTP on Mozilla Thunderbird for the address redacted@outlook.be. Crucial Note: Incoming mail (IMAP) works perfectly with the same credentials, proving that the authentication and the password used are correct. ​Technical Data & Actions Taken: ​SMTP Configuration: Server smtp.office365.com, Port 587, STARTTLS (or port 465 SSL/TLS). ​Authentication: Using a 16-character App Password generated after enabling Two-Step Verification. ​Symptom: Systematic rejection of the SMTP connection (Command Error 12 or timeout). Other Outlook accounts configured on the same Thunderbird client and the same internet connection (Belgium) are working without any issues. ​Tests Performed: Complete purge of Thunderbird's password manager, alias verification, and full restart of network equipment. ​Conclusion: Since the reception service is operational and full access is functional via Webmail/Outlook App, the block is specific to the SMTP protocol for this particular account on the Microsoft server side. ​Request: Please lift any security restrictions or reset security flags for the SMTP service on this specific account. My mail for respons : [edited from public community support forum] @gmail.com

(PII removed by moderator)

My husband and I use the same internet provider activ8 and access it through Thunderbird. I have a new computer. Received a configuration code from Activ8 and I can receive emails but not send them. Get the message PEER USING UNSUPPORTED VERSION OF SECURITY PROTOCOL. THE CONFIGURATION TO MAIL.ACTIV8.NET.AU MUST BE CORRECTED. How do I do that? Activ8 says they can't help.

My computer suddenly started the above error message for multiple programs. The local computer shop was able to sort out what appeared to be the root cause and that recovered some things but I still needed to reinstall a number of programs.

The program I am terrified of reinstalling is Thunderbird. All my emails on five email accounts since 2011 are stored in TB and I naturally do not want to lose any of them.

The major problems are the computer is running Win7 Enterprise and I am 82 years old so I am prone to needing things spelt out in greater detail than many others.

Can anyone provide a way to reset the program permissions (preferable) or identify the best way to reinstall and still access all my historic emails?

Thank you

I am using Thunderbird 115.18.0 and Windows 7 professional (no snarky comments please).

All has been working fine for years, but in the last few days, strange thing have been happening:

In the pane with all of my email accounts, the ">" icon to the left of the first account has been disappearing. This meant I could not look at any folders, including Inbox, Drafts, Sent etc and handmade folders. Cured by closing and opening Thunderbird.

I now have two Archive folders, one called Archive, the other Archives. Both empty, neither can be deleted.

Periodically, when the ">" is present, selecting it (to "V"), the list of folders SLOWLY appears, one folder at a time.

Periodically, the bottom of the Thunderbird window, shows a 'downloading' message, of hundreds of files. Several GB of data has been downloaded over a couple of days.

Opening the Inbox folder, the pane with subject, correspondents, date etc has changed the sort order.

Sometimes, all of the emails in this pane have had their font underlined.

Nothing on my system has intentionally changed,

Any ideas what has gone wrong, and how to put things right would be appreciated.

Thanks,

I have been using Mozilla Thunderbird for decades and they have even contributed a small amount of money to Thunderbird periodically. Just within the last two or three days all of a sudden I have been unable to send emails with my phone. I receive emails, but I do not send them. So I opened up a laptop where I did not have Thunderbird and set it up properly through Spectrum using the incoming and outgoing servers as mail.twc.com. and yes, just like on my phone. I continue to receive new emails, but even with the laptop I was unable to send an email. I received the message"send message error sending a message failed. The message could not be sent because the connection to outgoing server smtp mail.twc.com was lost in the middle of the transaction. Try again."I contacted Spectrum twice and both times they had me try to send a message through their Web server spectrum.net and that message did go through. Of course then their response is that this has to be a problem with the third-party app meaning Mozilla Thunderbird, and they can’t help with that at all. I sure would appreciate some help because I hate to walk away from Thunderbird as well as change my email address after all of these decades.

Continuation of my prior post: https://support.mozilla.org/en-US/questions/1516342

Thunderbird has a routine problem with being unable to log into various mail servers. I have four accounts and they all seem to share this problem.

Most recent update: I've tested this in Windows Safe Mode, and the problem has not appeared. Since I can't do any useful work in Safe Mode, it's hard to give it a thorough test, but so far so good. Also, I have removed AVG antivirus because it was redundant. I have seen no improvement since it was removed.

Can this problem be resolved?

I am running Thunderbird 147.0.1 (64-bit) on Windows 11 Pro 25H2. I have Thunderbird set up with two email accounts -- gmail and outlook.com (an old msn.com address). Approximately every 10-14 days the msn.com account encounters an error with the message "Command Error 12." When this happens, Thunderbird immediately drops all the local email folders for the msn.com account, and attempts to redownload all email and folders associated with the account. The msn.com account in question is configured for IMAP:

server name: outlook.office365.com Port:993 Connection Security: SSL/TLS Authentication Method: OAuth2

The expected behavior here would be for Thunderbird to display a connectivity error message but retain all local email on my laptop. However, this specific connectivity issue is dropping all locally stored email. I also noticed that the mail columns get reset to default. It appears this issue is causing Thunderbird to delete not just the email but some of the account configs as well.

At present, I do not have a screenshot showing the command error 12 message. I will try to take a screenshot the next time the issue occurs. What is not clear is whether this is an account setup issue or a bug in Thunderbird. Any advice would be appreciated. Thanks.

I can't login to one of my email addresses. It says login to server with username failed. I tried all of the suggestions (using a pop server for example) and none of them seem to work. Please help.

Folder name: BOGUS AI PRAISE-MKTING-BOOK CLUB BULLSHIT I had been adding emailed marketing messages that I knew were fake into this folder for about two weeks. This morning, after a Windows 11 Update, when I tried to add another such message to that folder, the entire file folder was missing. I tried everything I could think of, including looking for help online, to no avail. This folder contained around 500 emails, over 200 of which I hadn't even opened.

I'm trying to find the proper way to revert back to the default location for local mail message storage in TB (ver 140.7.1 esr).

Years ago I set my local message storage to a storage drive on my Win10 PC. I now want to move all of TB to a new Win11 PC but realize I have thing in 2 places - messages on my storage drive and everything else of TB in the default C: drive location.

If I simply change the Message Storage Local Directory back to the default path - will it move my current/old messages to the default location or do I have to manually move things (first or after?)?

I have many years and about 13Gb of email messages that I want to ensure I keep.

TIA