Thunderbird Community Forum

I must be doing something wrong. I am new to thunderbird, migrated from Eudora since I can't send mail with Eudora anymore.

I tried to configure Thunderbird as much as possible like Eudora, but ... it doesn't receive nor send mail. On the surface it looks fine, it seems thunderbird logs into the server, it seems it sends mail and checks for new mail, only I don't receive anything, nor send anything even though it looks it does. So what am I doing (or is going) wrong? (I can still receive mail with Eudora and today I checked and received 54 mails, none with Thunderbird)

Two nights ago I uninstalled ExpressVPN from my system at the instruction of one of their "support" people. My computer immediately lost the ability to access half of the websites I tried to visit and Thunderbird wouldn't send or receive email. I rebooted and that fixed every issue, but since then, Thunderbird no longer checks for new messages for any of my accounts. If I manually instruct it to check, it downloads the messages with no problem. I don't use any add-ons, and I'm using the latest version on a Windows 11 PC. I have already tried deleting global-messages-db.sqlite, repairing each mail folder from within Thunderbird, clearing the cache, and running an install of the latest version. I have also tried changing the setting for each mail folder to alter the interval for message checks by a minute just to see if that would jog it, but no luck. I've looked at various other help threads for this and am out of ideas. Thanks in advance for any help.

Hello,

I just switched to Thunderbird from Outlook and so far it seems nice but one problem when I click on the get messages cloud icon on the top left of the screen I receive no incoming messages. Now if I go to one particular email account (I have 8 email accounts) and right click and left click on get messages, new messages come in.

So my questions is, why doesn't all my mail come in when I click on the get messages icon? Am i misinterpreting this?

Thank you!

I have been using Thunderbird to access my comcast emails. I never had a problem with it. However, this afternoon, just out of the blue Thunderbird cannot download my emails, the following message popped up: "Login to server mail.comcast.net with username xxxxxxx failed." Then Thunderbird asks for a new password. When I enter the still correct password, it displays the same error message. I did not change anything in the settings before this error message popped up. I tried ChatGPT to get some answers, but whatever I changed it had no effect. I am attaching a screenshot of the server settings (I have of course removed my username). I would be grateful for any advice as to how to fix the issue. Thanking you.

Yesterday I opened Thunderbird to find that it was trying to download 8205 emails. 15 emails actually downloaded, there were no messages in SPAM folder. The notification at the lower right showed 300 more had 'downloaded' before I shut off the internet, went into Safe Mode, ran a virus check to find no threats found. No SPAM was recorded in Thunderbird when I went back online. There were, however, several files with large attachments so I don't know if this is a glitch regarding data vs. actual number emails because when I checked for updates (see attachment)

I discovered that since Version 115.4.2 I HAVE NEVER BEEN NOTIFIED OF UPDATES OR *FAILURE* TO UPDATE. AUTOMATIC UPDATES have been turned off and will remain turned off due to nearly dialup speed lack of bandwidth. I will abandon Thunderbird for having a fatal programming defect before turning on automatic updates.

My actual email provider did not show 8205 additional emails so I am concerned about a possible malware backdoor. Today 15 emails downloaded while the little notice at lower right said it was trying to download 113 ghost emails. I shut off Thunderbird and came here to post the problem. I will update Thunderbird, but need to know if there is a temporary file cache or some other hideyhole that the ghosts (or some attacker) might be storing godnosewhat so that I can either quarantine or delete them?

When I start Mozilla it checks for new mail. It always says no new mail. When I click on get messages if there are any new ones I get them downloaded. Why doesn't the first check find new mail as it used to? Thanks

Hello,

I have problem with this following message: authentication failed when connecting to imap.gmail.com. Nothing changes in my computer but Thunderbird from today 14:00 displayed this message and is not possible read new messages - it looks like not possible to load the message text.

Thank you

Thunderbird can receive emails but I cannot send them. I get the error message per the screenshot below concerning SMTP.

I have a MacBook Air with Mac OS Sequoia 15.7.2. The error started yesterday (21 November). Just finished conversing with Optus support and they say that it's not at their end: webmail works okay, can receive email and send it (will note there was a brief hiccough earlier today when could not send from webmail, but okay now). All settings as recommended (port for incoming server actually different from what Optus recommends, but when I changed it from 995 to 110, Thunderbird stopped being able to download emails, so changed it back again. Port for outgoing is as recommended, 25.) I tried lowering security, as suggested by Thunderbird help list, and no change so restored it.

I have the latest version of Thunderbird for Mac, 145.0.

My partner, who also uses Thunderbird, cannot send emails either. He has an older Mac running an older OS.

I have included two images, the second one showing details of selected server. When I clicked 'fetch certificate' it failed. Does that signify anything important?

The error console shows a lot of information, which of course I cannot understand, but can screenshot some of it if that would help.

No firewall, no virus protection, no VPN.

Any ideas as to what might be going on?

when sending email, I get this message "Your message was sent but a copy was not placed in your sent folder ([edited from public] @optusnet.com.au) due to network or file access errors." I would like some help to resolve this. Thanks

Since Fri evening 28 nov 2025, i can receive but not send emails at my PC I am with Optus in Australia and have contacted them multiple times and they assure me its not their end, but that they have been getting lots of calls so directed me here. I can receive and send emails directly via their webserver and can receive on the PC but sending times out I see a few posts in the last days saying the same thing re OPTUS so just reporting my settings are as per the OPTUS help desk

Server mail.optusnet.com.au Port 25 user ******* Authentication Normal Password Security STARTTLS

and i have deleted and rebuilt by TBird account several times ( as suggested by them ) but no luck

Andrew

For the past month or so, Thunderbird has stopped providing me with emails as swiftly and reliably as it has been for many years. When starting the application; In the bottom of Thunderbird I can see it seems to do all the checks to the mailservers correctly, it just doesn't download any new emails. Nine out of ten times, it doesn't work. Then, all of sudden, once in a while, it actually does work. It's really irritating and I'm considering switching to another mail application. Currently, I can access my mail by logging on to the webmail, but it would be so much nicer if Thunderbird would work just as it is intended. Kind Regards from a user in Denmark, Scandinavia. Version: 140.5.0esr

I have Thunderbird 145.0 (64-bit) running on an uptodate installation of Windows 11 and have recently found that the email in folders do not always order themselves in the way they are supposed to. Although I have all my folders set to show emails in date order, with the newest at the top I am now sometimes finding new emails halfway down the list. This has happened several times in the last few weeks. I have "repaired" the folders every time I notice this but it has not solved the problem. Is there a glitch in the later versions of Thunderbird which is causing this? It was apparent today with my 'deleted' folder. I can't send you an image because I have now sorted the issue, until it happens again. I only discovered this by mikssing a couple of important emails and finding them in webmail but not in Thunrderbird. I use IMAP and my settings to the server are correct.

Thunderbird was sending and receiving just fine until a couple hours ago. Now, I cannot send anything to anyone - including my email provider. The message is: "Outgoing server (SMTP) error. The server responded: (C18) RBL restriction: Blacklisted by Internal Reputation Service" I verified all the settings (though I changed nothing prior to the problem) and all is correct. I've checked with tech' support and they verified that my address does not have a Blacklist. I've restarted the program and restarted the computer. I've also donated several times to Thunderbird. Before I change clients, I thought I'd see if anyone had a fix for this. Thanks, D

I want to block a sender. The advice on line is to right click the email and create a filter. When I right click the list that appears has no option to create a filter.

How do I block an email, please?