All Products Community Forum

Reguarly with some month between I can´t send email. After many days, which is impossible to use, it is ok without doing anything.

Haven´t manage to send in many days and now it is huge problem.

When I click on send buttom on the email come text about the fail which is 100% wrong.

It say: An error occurred while sending mail. The mail server responded: (then come my email adress): Sender adress rejected: not owned by (the part of my adress in front of @) Please check the message recipient (my email adress) and try again.

This text is 100% wrong because all things is as always! Never changed it. And seeing it in setting it like it should be!

I am almost given up, this come always with months between and that is hopeless.

Please 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.

Hello all:

Transferring Thunderbird from the system above to the system noted above. Follow the instructions from here on the Mozilla Support page (copied both "Thunderbird" directories into the Roaming and Local destination directories. When the destination machine installation opens, it is functional (i.e. it picks up all the existing e-mail accounts, downloads new mail, etc...). The problem starts when we get to the local folders.

All of these have a date and time appended to them in the destination installation. For example, if the original folder is "Prosperity Bank" the destination folder is labeled "Prosperity Bank (2025_09_21 23_06_33 UTC)" and will not let not populate (shows no messages inside).

As I am typing this, it seems I may have identified the problem (or at least part of it). It seems the destination system install is slowly working its way through the local folders randomly (not in alphabetically order), as it seems to be slowly populating them with the old mail stored therein on the original system. It is going very slowly. Very slowly.

Has anyone else experienced this? Is it normal? Is there any way to quickly eliminate the dates now appended to the local file names? (Visually this is very annoying and I do not want to try modifying the individual folder names yet until I'm sure its populated as much as it will populate.)

Thank you for any assistance.

Larry Reese

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.

Please Please Please advise how to modify settings to stop copying emails to "All Mail" folder. There are nearly 14K emails in that folder, and it's killing my capacity, I'm getting warnings, etc. Yes, I'm using Gmail.

Yes, I have unsubcribed from it, starting from my account name → Subscribe → unchecked [Gmail] All Mail. To no avail...

Of course, I do not want to delete mails I have saved in my hundreds of other folders. My mail goes back 25+ years, and I want to keep those archives.

Thank you Thank you Thank you!

I had two Thunderbird apps on my computer. When I realized that one of them was for organizations, which I don't belong to, I deleted it. But both of the apps were deleted. I then reinstalled Thunderbird, but when I went to send an email, my entire address book was blank. How do I retrieve it and reinstall it ? Thank you.

i do use ad blockers "experiencing problems find out why "well,of course lol. I know this ,but when i shut down the browser & re launch the browser it won't initiate/execute. not matter what I do. I then run the DISM script and she (firefox) fires back up again. Any insight or work around to fix this this nagging problem would be greatly appreciated. Yeah, windows 11, 32 gig of ram, 60 mps down 75 up.

I appear to have my bookmarks duplicated. Bookmark Menu list of bookmarks, bookmark 1

                                                           bookmark 2
                                                           bookmark 3 etc
                                                           ........
                                                           bookmark 1
                                                           bookmark 2
                                                           bookmark 3 etc

At a glance, the repeated bookmarks are the same, but I could have filed a new bookmark in either set. What can I do to stop these duplicates?

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?