Thunderbird Community Forum

I choose to use POP not IMAP. Yesterday morning, messages downloaded as normal, no problem. Yesterday afternoon, they did not download and I received this message "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." I had done nothing at all to my system in the meanwhile, as far as I am aware. I have tried deleting a lot of old emails from my inbox, and emptying the 'Deleted' folder. Any suggestions very welcome.

I have the latest T-bird installed on a latest version linux Mint laptop and occasionally get puzzling errors on Yahoo mail.

Mostly it all works, but Yahoo email errors are often enough to be bothersome and I can't find any information on the rather obsure errors. Been this way through many t-bird and Linux releases.

My other email accounts don't seem to have a problem (gmail, outlook) on any t-bird instances. Just Yahoo mail on Linux Mint t-bird. Here are the errors:

"Please try later" and apparent timeouts on Yahoo mail (on t-bird, of course). This is obvious, but it doesn't happen on my Win 11 and Android T-bird programs.

Operation on yahoo "inbox" did not succeed. Yahoo mail server responded "p." (Yes, just "p.")

Operation on yahoo "inbox" did not succeed. Yahoo mail server responded "UID FETCH completed"

These errors don't seem to happen on Android t-bird or Win 11 t-bird on the same accounts, but I'm not on those for very long.

Any guidance would be appreciated.

Yes, this outlook account was made earlier this year. I've tried all of the "fixes" offered on here and across the internet. I'm changed to to password and got the app password. I've deleted 2FA to see if that would work. I've deleted the Oauth key and it refreshed to a new one. I've done it all and TB-sync is not available to me cus apparently now i'm right outside the app version limit.... how convenient. It's very frustrating as i really like the app and still use it to read my emails but it's very annoying to have to open the outlook app and go through all that just to send an email. I keep getting told it is possible, i've been battling this on and off for months. I cant just get a new email either as i already swapped everything to the outlook one and my work using out look as well. i am able to sync my calendar even but apparently just not my outgoing emails. I would like to transfer my email but the other email i have is a proton email and they are a whole other headache. Please help.

OS: Linux / Android

TB Version: 156.0

Current Outgoing Server Setup:

Server Name: smtp-mail.outlook.com Port: 587 Connection Security: STARTTLS Auth Method: OAuth2 Username: *****@outlook.com

Mail sent to me as cc: and/or bcc: addressee (but not as a To: addressee) is received at my ISP mail account, but Thunderbird will not retrieve them.

This has been going for a long while it seems, but I don't get much mail addressed as cc: or bcc:, so I only recently became aware of it.

My ISP webmail interface uses Roundcube. Cc: and bcc: messages sent to me show up there. I have Thunderbird 156.0 installed on two macOS 27.0 machines and Thunderbird 24.0b2 installed on Android 17 (includes all updates through Android security update of September 5, 2026). Neither of the three will retrieve the cc: or bcc: messages, but all other e-mail functions work as expected.

My ISP says it's a Thunderbird problem, but I ain't so sure. Any ideas?

“My Spectrum email address is [redacted]@charter.net. Spectrum webmail can send and Thunderbird can't receive or send. The outgoing server is mobile.charter.net and the connection times out. I tested the connection from my computer and ports 587 and 465 both respond successfully. Thunderbird is set to No Proxy. when i tried to send today, it gave me this message, "Sending of the message failed. The message could not be sent because the connection to Outgoing server (SMTP) mobile.charter.net timed out. Try again." i contacted spectrum about this and now when i try to send, it says nothing and the message never arrives.

I created a POP3 account, and no SMTP config was crested in Thunderbird. So, I tried the Add option and after filling the form the line still did not get created. Current TB version, Win 11 Pro. I have several other accounts that configured OK, all Spectrum.

I am starting have problem with Yahoo mail interface with thunderbird, It is not updating yahoo mail. I stared to get message " Connection to server Pop.mail.yahoo.com timed out". What is the solution? I checked server port (995) number and Thunderbird is upto date.

Any help is appreciated

I cannot connect Thunderbird to a primary outlook.com account. I can connect to an outlook.com alias account. I have confirmed this on two Windows 10 machines. I can connect to the primary outlook.com account from an iphone and an ipad. Is Thunderbird broken?

I use Windows 11 Pro on a desktop computer. I use Firefox (which is up to date) and Thunderbird as my email client (which is up to date). I use Zone Alarm Extreme Security as my Firewall and Anti Virus

Recently it has become a nightmare sending and receiving emails to my markhowes@btinternet.com email address. Sometimes the emails (which I know are on the bt server) don't arrive but I don't get an error message. Then later in the day I might receive loads of emails at once.

Sending emails is even more of a problem. They simply don't go. Sometimes I get a time out message, sometimes I get an incorrect password message.

Within Thunderbird there is an option to check connection to both the outgoing and incoming bt servers. Usually (but not always) connection shows as "successful".

This has been going on for a couple of months - maybe it's a coincidence but it seems to start up after a Windows automated update and then things settle down again (I think) until the next Windows monthly update.

I'm not all that computer literate so please don't suggest messing around with the Registry or other very technical solutions but if anyone can help me solve this maddening problem I would be really grateful.

I can send and receive emails on my Android phone and directly on the bt email site via my Firefox browser.

Mark

This morning, I go into Thunderbird, but while I can see all my previous emails and folders, there are none from today. And yet going directly to TalkTalk Mail, there have been some. What can I do?

Emails work fine through everymail but using the thunderbird front end not working. Upped timeout to 1000 Message connection to outgoing server timed out Deleted browsing history.disabled antivirus no improvement

Ive been sending a weekly invite message from Thunderbird to same 40 recipients - no prob until today, when i got this message:

Sending of the message failed. The message was not sent due to exceeding the allowed number of recipients. The server responded: Policy-SC01 You’ve reached your sending limit. Don’t worry, you can send again soon..

I contacted Virgin support who shared my screen and played around with some of the Thunderbird settings. No solution so they said contact Thunderbird support, hence message. At time of this message i cannot even send to one recipient......would appreciate advice on here if possible.

Aloha. I'm helping a friend with setting up a new Windows 11 PC, and cannot get Thunderbird to connect to Spectrum's servers. I spent an hour on the phone with Spectrum support and they just gave up and said it must be an issue with Thunderbird. Here are the details:

- Brand new Dell 24 All-in-One EC24250 - Windows 11 25H2 plus all additional fixes. - All Dell drivers updated. - Thunderbird V155.0 64-bit

If I click on 'Get Messages' after a while I get: "Connection to server mail.twc.com timed out". I've gone into the config editor and changed mailnews.tcptimeout from 100 to 500 and still get the error.

In the Account Settings | Server Settings | Test server connection I get: An error occurred connecting to mail.twc.com:993.

I've tried this with both setting up a brand new account in Thunderbird, and also via copying the 'Thunderbird' folder from %appdata%\roaming from her old machine.

Email configuration (from Spectrum).

IMAP Settings Server name: mail.twc.com Port: 993 user name: abcd@hawaii.rr.com Connection Security: SSL/TLS Authentication method: Normal password

SMTP settings Server Name: mail.twc.com Port 587 Connection Security: STARTTLS Authentication method: Normal password

Can anyone help me troubleshoot this scenario?

Mahalo, Harry Z

Can't send emails on my computer on internet out of fredfam@frii.com since about 8/23/26. Couldn't solve problem. Added my Gmail account to Mozilla about 9/5/26 to keep being able to send some emails. Sending in Gmail failed since about 9/9/26. Problem somewhat corresponds to update of Mozilla 153.1.0. I still receive incoming emails on Mozilla laptop for both email addresses. On 9/13/26 all my Mozilla calendar events disappeared for several months and when I enter new events now, they disappear next time Mozilla loads. Running Windows 10, have not had such problems before. I've checked and changed Port settings many times, no result. My router provider detects no problems with internet connection. Is the OAuth process causing the issue with sending on outgoing server.

I have 2 Android phones. Both phones send and receive fredfam and gmail messages correctly between phones when having good tower contact. My gmail web browser account correctly shows send & receive. My FREDFAM web browser correctly shows send/receive messages.

My computer, Mozilla, receives messages sent by either phone for both email addresses.

I've had Mozilla software updates series 153.1 thru 153.2 from 8/23-9/2/26.

I had to use my Gmail password to enter this help system as my password for my FredFam account or password indentifying my laptop would not work to enter this help system. Something seems really messed up in my Mozilla setup/version. Thanks, Dave Freddy

Have been working with NameCheap's Private Email (PE) support for a couple days trying to unsubscribe and hide or delete folders Deleted Messages, Junk, Sent Items and Sent Messages.

Today a chat rep for PE told me these are not native PE folders and were created by a client app. If this is true and as TB is the only client I ever use it would have to be the culprit.

Notably, there remain a couple of unaffected email accounts, one of which is only accessed from an old 68.12.1 (64-bit) machine.

The rep is going to look into removing the folders on their end and I am going to revert to the old version of TB for my machine to see if we can clean up this issue.

Is it possible that newer versions of TB are really creating the unmanageable folders and is there any way that can be stopped???

Have used TB for years, love it and contribute to its support but while these folders appear at the bottom of the list in PE's web client they are inerspersed with the normal (Inbox, Sent, etc) folders in TB and they sometimes have duplicate names (i.e. Sent and Sent Items both appear as "Sent" in TB with only the Properties Dialog showing which is which). Very confusing and pretty much a deal breaker for TB.

When replying to an email or sending a new mail I get the message :- An error occurred while sending mail. Server responded : You need to authenticate when sending mail from (ip address) Please check "message Recipient" and try again. How do I authenticate ? Thanks140.7.1