Bidhaa zote Community Forum

For a few weeks now, sent emails have not been appearing in the "Sent" folder. The recipient receives the email, but I have no confirmation in "Sent" that it was actually sent. It was never a problem.

Attached is a picture of what my account settings looks like. Thunderbird stopped syncing my emails from a gmail account. How do I get it to continue syncing my emails?

I have used Thunderbird for years with complete success. Recently (within the past month) I have lost the ability to send (SMTP) mail and receive the following error message: "Send Message Error, Sending of the message failed. Unable to authenticate to Outgoing server (SMTP). Please check the password and verify the 'Authentication method' in 'Account Settings | Outgoing server (SMTP)." [I just change my from address to another one going through Network Solutions and the mail sends just fine.]

Everything seems to be in order when checking my settings. I finally called Yahoo and spent an hour on the phone with them, including a supervisor (in the background) and they were unable to correct the situation. Yes, since I had called them from their tech support line (I looked it up; did not call anything sent to me) and they worked on my computer trying to fix it. They finally said it was a Thunderbird issue and said I needed to contact Thunderbird.

I am able to send from my phone (Android) using the same cox.net e-mail address. My wife is able to send from her computer using her cox.net via Thunderbird. My wife's incoming mail is IMAP while mine are all POP.

I happen to have several cox.net accounts and get the same SMTP error on all. However, all receive POP mail just fine, but see the next paragraph.

[As an aside (?), I should note that after Yahoo attempted to "fix" the problem, ALL my incoming cox.net mail comes into ALL of my cox.net accounts regardless of which one is addressed.]

I don't even know where to start at this point. Thanks for any help.

Bill

Sans aucune raison ni manipulation je n'ai plus de mails dans Thunderbird

J'ai quitté l'application, redémarré mon MacBook et rien n'y change. Quand je vais sur le webmail j'ai bien la totalité de mes mails. Par contre j'avais un dossier local et du coup je n'y ai plus accès non plus

After returning from a 6 day vacation, my wife attempted to download email from her Yahoo email account. There are nearly 200 messages that have piled up but they aren't moving. I've uninstalled and re-installed TB. I've uninstalled and reinstalled the app password in Yahoo. There is no problem with accessing the email via any web browser. I spent 49 minutes on a tech support call with Yahoo and they have said the problem is with TB because they repeated the same steps I have. I checked firewall settings and the only antivirus program on the computer is Malware Bytes and it's not running in the background. The version of TB is the most recent as of yesterday. I don't see any sketchy looking emails in the web version of Yahoo Mail when it's opened. It's set up as a POP3 account and has been since Cox Internet gave their email over to Yahoo. I'd appreciate any assistance in resolving this because it's currently above my pay grade and tech support at Yahoo.

On my iMac, across all thunderbird email accounts, when I click on "New Message", the new window opens up with the Send button and Encrypt button blanked out. To activate the Send button, I have to right click on the Send button, then click on "Customize..." button, then click on "Restore Default Set". Next new message, same drill. This started one day ago and is a pain in the butt. How do I make the Send button live permanently?

I started a monthly donation to Thunderbird a few hours ago and now I'm thinking it may have been a scam. Not sure, and I have sent an email to your donation email about this. Since I made that donation (and maybe this is a coincidence), I am not able to send any emails. I can compose an email, but there is no "send" button anymore. Can you help me with this? Thank you very much.

Bug report 15 Aug. 2026

The disappearing emails.

It took me a while to find out what was going on. My friend said some of his Sent mail was nowhere to be found. After searching for it in a 'wrong' place it does not exist. Sending to the same recipient and again it just disappears. Simplifying the mail down to just address and the word "test", it still disappears. No combination of a Thunderbird search nor an Everything search finds anything. No return error message from this provider nor the recipients.

This address is for the local electricity board, other mails to other departments

go through correctly and are found in the Sent email directory.

A careful inspection of the contact information shows this is the only department

without a "Shown Name" it only has an email address filled in.

Entering a Name for this contact solves the problem, it now shows up in the Sent

folder and is easily searchable.

I hope this explanation helps some one else with a 'Houdini' email.

My Thunderbird email account no longer lets me send out messages. I get a message error

  QUOTE____

Sending of message failed. An error occurred while sending mail. The mail server has responded. Message contains bare CR and is violating 822.bis section 2.3. Please check the message and try again.

But I am able to receive messages.

Can anyone help. Thanks in advance!!

bob.fannon

Feb 14, 2026, 13:01 CST

I have used Thunderbird for a number of years with Plusnet (using POP settings) in the UK. However, Plusnet has transferred their support to a company called Greenby who have made a hash of it and offer very poor support. So, I want to use Outlook as the mail server but I am unable to send any messages via Thunderbird to the Outlook server. I can however download messages with no problems. The error message I get is :- Sending of the message failed. Unable to authenticate to Outgoing server (SMTP) smtp.office365.com. Please check the password and verify the 'Authentication method' in 'Account Settings | Outgoing server (SMTP)'

My default Outgoing Sever settings are :- Server Name : smtp.office365.com Port: 587 User Name: bob.fannon@outlook.com Authentication method: OAuth2 Connection Security: STARTTLS

I have tried deleting the Thunderbird account and re-creating it but still got the same result. I also tried to use my old Icloud account ( having first setup my App Specific password) but got the same result.

Hi David This is the last attempt I did but it failed. Enclosed is the screen shot you have asked for. Keep in mind my WIN 10 has 64 Bit but the last update from Thunderbird was 32 Bit

Heinz

I am using Thunderbird Meadow.

Is it possible to send emails without a subject, other than getting the warning dialogue box.

It would be very useful.

Thank you

Hello,

I have been using Thunderbird for years without issue, but three days ago, I started having issues.

Now, I don't receive emails when I open Thunderbird. If I delete my password and re-sign in, I receive emails, but cannot send them. Trying to send an email makes Thunderbird ask me to sign in again.

I have two email accounts that I use with Thunderbird. Both accounts have this issue. I have this issue regardless of the network I'm in (work, cell hotspot, or home).

Things I have tried:

• Verified that my IMAP and SMTP settings match the guidance from email servers.
• Verified that my computer firewall is not blocking email.
• Tried connecting on different networks (so different ISPs)
• Deleted and re-entered passwords for each account

Here my current server configuration:

• Email 1 (@gmail.com)

 * Server Name: imap.gmail.com
 * Port: 993
 * Connection Security: SSL/TLS
 * Authentication Method: OAuth2

• Email 1 Outgoing Server:

 * Server Name: smpt.gmail.com
 * Port: 465
 * Authentication Method: OAuth2
 * Connection Security SSL/TLS

• Email 2 (@[university].edu)

 * Server Name: outlook.office365.com
 * Port: 993
 * Connection Security: SSL/TLS
 * Authentication Method: OAuth2

• Email 2 Outgoing Server:

 * Server Name: smtp.office365.com
 * Port: 587
 * Authentication Method: OAuth2
 * Connection Security SSL/TLS

I will greatly appreciate any help you can provide!

I've never had a problem before but suddenly I'm getting an error when I try to log into one of my accounts telling me "The STAT command did not succeed. Error getting message number and sizes. Mail server pop.gmail.com responded [AUTH] invalid credentials. Why is this happening now?

I have 4 other accounts on Thunderbird and this is the only one that has started giving me problems.