Thunderbird Community Forum

Each time I attempt to login w/ T-Bird, google mail gives me this message:

400. That’s an error.

The server cannot process the request because it is malformed. It should not be retried. That’s all we know.

Please see attached image of the problem.

I have tried looking on Google for ideas but have not found anything on this or how to fix. Hope someone can please help would be amazing!

Google -

400. That's an error

The server cannot process the request because it is malformed. It should be retied. That's all we know.

For a week or two I haven't been able to send any email from Thunderbird. I use smtp.gmail.com as my outgoing server, and have it configured using SSL/TLS on port 465 with Oauth2 authentication. I first saw this on an older TB version, but have now updated to Thunderbird 152.0.1 on MacOS Sequoia 15.7.7.

When I try to send email, a dialog pops up saying "Enter credentials" for my account, then "Verify it's you". When I click on Next it asks me to "Complete sign-in using your passkey". I believe at this point another window is supposed to pop up and I can use a fingerprint to enter the passkey, but that window never pops up. I have tried 3 different default browsers: Firefox (my usual one), Google Chrome, and Safari. All behave the same. Firefox might be suppressing Javascript, but the other two certainly aren't.

Is there some system security setting that might be preventing Thunderbird from opening a window in the default browser, or does Thunderbird maintain its own record of the browser? Any other suggestions on how to get the passkey challenge to appear?

I use Thunderbird as a POP server and keep some historic read emails in my inbox as well as archiving others to local folders. I am moving to a new windows 11 computer from an old windows 8 computer. So I exported my Thunderbird profile on the old computer, copied it across to the new computer, installed Thunderbird on it, then imported the profile. All my local folders are there with their historic emails, but there are no read emails in the inbox, only the unread ones ?? Be grateful for any explanation of why this is and how I get them back. thanks Martyn Jones

I recently migrated from a much older version of Thunderbird where I had been using the Mail Merge add on. In 151/152 most of the variable fields are no longer recognised. Below is the list provided by the developer. I can only get FirstName LastName and PrimaryEmail to merge correctly I troubleshot with Custom1 JobTitle and Nickname to no avail. I've emailed the developer. I suspect Thunderbird has changed the names of the fields in updating the Address Book. Has anyone got a current list of variables for Thunderbird since the Address Book has been rebuilt? Thanks, Greg

{{DisplayName}} {{FirstName}} {{LastName}} {{NickName}} {{NamePrefix}} {{NameSuffix}} {{AdditionalNames}} {{PrimaryEmail}} {{SecondEmail}} {{HomePhone}} {{WorkPhone}} {{CellularNumber}} {{FaxNumber}} {{PagerNumber}} {{HomeAddress}} {{HomeCity}} {{HomeState}} {{HomeZipCode}} {{HomeCountry}} {{WebPage2}} {{WorkAddress}} {{WorkCity}} {{WorkState}} {{WorkZipCode}} {{WorkCountry}} {{WebPage1}} {{JobTitle}} {{Department}} {{Company}} {{Custom1}} {{Custom2}} {{Custom3}} {{Custom4}} {{Notes}} {{BirthYear}} {{BirthMonth}} {{BirthDay}} {{AnniversaryYear}} {{AnniversaryMonth}} {{AnniversaryDay}}

Hi,

I use Thunderbird 152.0.1 (64-Bit) and I only have three items in the files & attachment section of general settings (JPG, PDF, Excel). How can I add more items, for other file types? Is there an easy way to do this or does this mean I have to deep dive into the configuration of Thunderbird?

And would it be possible to add an item to declare that website links in e-mails have to be opened with Firefox in private mode, which is not the standard browser on my machine?

Thx!

duplicate of /questions/1591698 thread

I have Juno Email Accounts ; What are the Settings ? ... Incoming, Ports, Outgoing, Ports

Mozilla Thunderbird Will Not Install on Win10 Machines ... The Auto Settings Algorithm has issues.

Email Address : [edited] @Juno.com - TextMail : [edited]

/edited email and phone# from public community support forum

To my new computer Thunderbird has just fetched the INBOX-mails from the IMAP-server, not my many subfolders, not the SENT-folder, not the SPAM-folder. This has previously worked when I changed to a new computer. How do I get Thunderbird to transfer these mails.

Email problem. Old Lenovo Desktop, Window 8.0 (I know, I know, but it's my wife's and all she uses it for is email and utube recipes, and she's used to it). I use it for some banking, mainly because the printer is on it. Tbird 115.18.0 (32 bit) -says it's up to date AVG antivirus free

Email through yahoo. It worked fine until, going by the last date it linked email, 10/30/25 at 06:45AM MST When I tried to download new messages Sunday 11/2, it failed.

It pops up a new window "Enter credentials for bababarb@yahoo.com on imap.mail.yahoo.com" In the address window is "https://login.yahoo.com/?src=thunderbird&client_id=(about a zillion characters) Then, in the message window is "Edge: Too many requests"

So, I did the troubleshooting as in Help article. I logged in on the webmail, signed in with the password, and was able to see the messages, many from after the 30th (she gets a ton of sorta spam).

Looking under Account setting> server settings, I find that the security is set to SSL/TLS and Authentication is set to OAuth2. Incidentally, these were set automatically when I set this to a yahoo.com address.

So, I try setting the Authentication to Password and request mail. I get a popup asking for the password. I enter it (the same password I used on webmail) and it replies "Login to server imap.mail.yahoo.com with username bababarb@yahoo.com failed."

Following suggestions on the help article, I got to Settings, and check "saved passwords". Then, again following the suggestions, I remove the yahoo password entry. According to the article, the next login attempt should ask for a password. It does not. I just get the "too many requests" popup. What the hell, I go back and remove the SMTP password, too. Same result.

Anybody else having this issue? Any suggestions?

Something changed. I’ve tried to set up my old AOL email account multiple times using different default browsers, and the setup typically fails. Using Edge, I get “Edge: Too Many Requests” . Using Firefox, I get “Waiting for authorization in login popup…” and then the old rotating arrow. After about a minute delay, the Account Hub reports “Authentication error.” The Thunderbird Account Hub reports the outgoing server settings test good. I’ve changed my AOL email password, and have an AOL application password ready to use, but never get asked. I’ve turned off two-step verification in AOL, but same Thunderbird behavior. I’ve got multiple computers, and this issue is the same on all. I’ve had no problem adding a Gmail and SBCGlobal.net account. Thunderbird is 144.0.1 (64-bit) release. Windows 11 Home, version 25H2. I really don't want to give up Thunderbird, but I need this account badly.

When I try to add a new Mail Account, the "Looking up configuration" step hangs indefinitely. I have to force a hard exit to reopen the app. I was able to add my hotmail account without issue, but now that I'm trying to add @yahoo.co.uk , it just freezes up. Thx

Windows 10, newest Thunderbird.

Yesterday I changed my AOL password online. Now Thunderbird email no longer works. I get a popup labelled "enter credentials for user on pop.aol.com". Within the popup window it says "Edge: Too Many Requests"

Settings have not changed and worked prior to password change. I believe if the popup window was working correctly I could enter my new password and all would be fine.

pop.aol.com 995 SSL/TLS OAuth2

smtp.aol.com 465 SSL/TLS OAuth2

Thanks,

Ed

I changed my yahoo password and can longer access this account in Thunderbird.

Now when I sign in to Thunderbird I get 'Edge To Many requests'

Unfortunately I deleted the yahoo user name and password in Thunderbird Password/ Saved Logins thinking Yahoo might automatically ask for my new password when re-starting Thunderbird

Can somebody help please.

Many thanks

Started getting error April 10. I have SSL/TLS and Oauth2 set for Thunderbird account server and smtp. Looked thru lots of web messages - no joy. Via web browser I can connect to my Yahoo email without issue. My gmail account on Thunderbird still works fine (with its unique third party password). I am on current Thunderbird release 115.9.0 (64 bit). I disabled the only add-on that Thunderbird was using. Windows 11 Pro which is up to date. Plenty of open disk space. Have rebooted my PC multiple times.

Looking for suggestions Thanks Bob

I have been using Thunderbird for many years. I have 4 accounts that have all been set up and working fine. This morning the 2 yahoo.com accounts stopped working. I logged in to the impacted accounts using a web browser and password just fine. I then updated Thunderbird to 116.0 to see if that would fix the problem, but it did not. The outlook and gmail accounts are working fine, for now.

When Thunderbird attempts to download mail for the yahoo accounts, I get a large pop-up window with "Edge: Too Many Requests". The pop-up window is blank except for that error message. I get the small pop-up with the Authentication Failure message. Sometimes I get Retry, Enter Password or Cancel. But I never see a window that will allow me to enter my password.

I can send/receive mail from the accounts while logged in via a browser but authentication fails within Thunderbird.

PRELUDE: I have several email accounts. All accounts display properly, except one. Yes, this is similar to my question about bottom of the far left [of emails] list of emails - but this is different.

On the far left of Thunderbird is a list of all my email accounts with "Inbox" etcetera. Each email account shows it's Inbox/Sent/Deleted/ except for 1 account. The problem email account only shows it's Title and Inbox northing else. Yes, I tested it and sent emails to it, and used the problem email account to send, create a draft, and they don't show..

The image explains it.

Thanks for reading this ~r

I have used Thunderbird for years. Suddenly it asks for my email account password every time I send an email message. What is the problem? The passwords for my email accounts have always been stored in my configuration and it never asked for them. Very annoying.