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SMTP/Sending Emails just stopped working

  • 23 replies
  • 5 have this problem
  • Last reply by Taomo

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Hi there - been using Thunderbird for donkeys (since it was Eudora!). A few weeks back I started to get messages from Microsoft that I needed to change security settings as they were no longer supported on 3rd party email handlers like Thunderbird. So I re-created the three accounts I had there and it seemed to be OK, though SMTP did not have the OAUTH2 option available ... and when I tried to use the new SMTPs they wouldn't work. So I reverted to the old settings there and it worked again.

But this morning, with the big update to Thunderbird Nebula, I can no longer send emails from the MS accounts. My Gmail one is still OK ... but whatever I try, I cannot get the MS ones to send emails - I get a failure connecting.

Login to server smtp-mail.outlook.com with username xxxxx@hotmail.com failed.

I checked on MS and the details shown there:

SMTP server name smtp-mail.outlook.com SMTP port 587 SMTP encryption STARTTLS Authentication Method OAuth2/Modern Auth

Are what I have (I did have a different SMTP Server name came up - smtp.office365.com - but that doesn't work either)

So ... where is the issue? Is this a bug in the new Thunderbird setup? Something else? I don't know where to go ...

David

Hi there - been using Thunderbird for donkeys (since it was Eudora!). A few weeks back I started to get messages from Microsoft that I needed to change security settings as they were no longer supported on 3rd party email handlers like Thunderbird. So I re-created the three accounts I had there and it seemed to be OK, though SMTP did not have the OAUTH2 option available ... and when I tried to use the new SMTPs they wouldn't work. So I reverted to the old settings there and it worked again. But this morning, with the big update to Thunderbird Nebula, I can no longer send emails from the MS accounts. My Gmail one is still OK ... but whatever I try, I cannot get the MS ones to send emails - I get a failure connecting. Login to server smtp-mail.outlook.com with username xxxxx@hotmail.com failed. I checked on MS and the details shown there: SMTP server name smtp-mail.outlook.com SMTP port 587 SMTP encryption STARTTLS Authentication Method OAuth2/Modern Auth Are what I have (I did have a different SMTP Server name came up - smtp.office365.com - but that doesn't work either) So ... where is the issue? Is this a bug in the new Thunderbird setup? Something else? I don't know where to go ... David

Chosen solution

To check:

  • Tools > Developer Tools > Error Console
  • Click on the top left bin icon to clear the console.
  • Close Error console

Then try to send an email and wait for the failure. Open Error console

Post image showing contents.

If you see something like this:

mailnews.smtp: Command failed: 535 Authentication unsuccessful, SmtpClientAuthentication is disabled for the Tenant. Visit https://aka.ms/smtp_auth_disabled for more information

The link mentioned in error console : https://aka.ms/smtp_auth_disabled

That link goes to this location - I specifically include the info on 'enable smtp': https://learn.microsoft.com/en-us/exchange/clients-and-mobile-in-exchange-online/authenticated-client-smtp-submission#enable-smtp-auth-for-specific-mailboxes

If you as a user are not enabled for SMTP then it fails - switch on SMTP. https://support.mozilla.org/en-US/questions/1464666?page=2#answer-1676928


IF you see something like the following in error console:

mailnews.smtp: Command failed: 535 Authentication unsuccessful [MN2PR05CA0041.namprd05.prod.outlook.com 2024-09-25T20:33:37.105Z 08DCDD14E4ECBF59]; currentAction=_actionAUTH_XOAUTH2 SmtpClient.sys.mjs:602:19

mailnews.smtp: Command failed: 500 Unrecognized command 'Length: 7' [MN2PR05CA0041.namprd05.prod.outlook.com 2024-09-25T20:33:42.231Z 08DCDD14E4ECBF59]; currentAction=_actionAUTHComplete SmtpClient.sys.mjs:602:19

This error message means issue with sending email address/username not matching primary. I asked user to check 'alias' email address. Some people may have a hotmail email address and also that hotmail account allowed some additional/alias email addresses. In outlook.com microsoft account webmail. You need to check what is set up as the primary and adjust if necessary. Apparently, smtp username in Thunderbird needs to use primary email address.

For more info and response from user who had problem resolved including images : https://support.mozilla.org/en-US/questions/1465652#answer-1680641

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See: https://support.mozilla.org/en-US/questions/1465555#answer-1676802

Those are the settings I use. Quite a few people seem to have trouble getting them to initially work.

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Thanks! But as I say, those are the settings I have ... I just get the login failure message every time I try and send an email :(

I've tried closing and restarting Thunderbird; rebooting the PC. I am on Windows 10 and everything is up to date ...

Oh, and the RESET PASSWORD doesn't do anything on the error message as well - I'm not asked to re-enter the password ... it sort of feels like a Thunderbird bug ...

David

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Do you know specifically what version of Thunderbird you upgraded from->to?

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Hi Corey - The Update this morning (22 Sept) was to Version 128.2.3esr - Nebula - which I note was released on 20 Sept (we've been away and so it didn't update until this morning).

I was on Version 115.15.0esr ... installed 8 Sept

(I found the Update History :))

Does that help?

David

Modified by david854

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what "other" smtp servers do you have? Is the outlook/Office one mentioned in other SMTP servers in account settings > outgoing servers (SMTP)

My observation is folk assume incorrectly that Thunderbird will only use the SMTP server specified in the identity part of their incoming mail account. Yjis is not the case. Others assume the "default" will bhe used and that is not the case either. Which SMTP is selected is a relatively complex equation based on what folder you have selected, what identity you are sending from and can include directives from certain addons. SO you can assume basically nothing

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Hi Matt

I *think* I understand the Thunderbird SMTP server thing ... just not why it's not working ... but your note suggests it's more complex and nuanced ...

On the ACCOUNT SETTINGS list for the two different MS accounts in question, there is on the 'top' level a field at the bottom with OUTGOING SERVER (SMTP) on it ... this has a dropdown to all the SMTP servers on the TB installation. So I have ensured that the one selected there is the right one for the account - it's not just the default one.

And the one that is selected has all the details as mentioned up top in my first note.

You can also see all the different SMTP servers in the TB install at the very end of the list at the left of the ACCOUNT SETTINGS tab ... and basically you can edit/change them from there if you want to, or you can also edit them from the selection list within the details for a specific account.

Is there something else which needs amending here? As I say, there are actually loads of SMTP 'accounts' in that list, I assume all from various additions of accounts to TB over the years.

The settings there I have for the two MS accounts that I'm trying to use are:

SERVER NAME: smtp.office365.com (but if I try and use smtp.mail.outlook.com which is what MS say you should use in their help pages, I get the same result - neither work) PORT: 587 CONNECTION SECURITY: STARTTLS AUTHENTICATION METHOD: OAuth2 USER NAME: the appropriate email address for the account

I can't find any other settings to change ...

As mentioned, my Gmail account is still working fine - it's just the MS ones which have stopped sending mail. I can still receive mail fine to all of them, and read it etc ... it's just when I try and send I get the 'Login to server smtp-mail.outlook.com with username xxxxx@hotmail.com failed' message (or the office365 server depending on which I use).

Oh, and you mentioned ADD ONS - I don't think I have any. None are showing as being there in the ADD ONS AND THEMES area anyway.

Thanks!!

David

Modified by david854

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Hi Matt

I *think* I understand the Thunderbird SMTP server thing ... just not why it's not working ... but your note suggests it's more complex and nuanced ...

On the ACCOUNT SETTINGS list for the two different MS accounts in question, there is on the 'top' level a field at the bottom with OUTGOING SERVER (SMTP) on it ... this has a dropdown to all the SMTP servers on the TB installation. So I have ensured that the one selected there is the right one for the account - it's not just the default one.

And the one that is selected has all the details as mentioned up top in my first note.

You can also see all the different SMTP servers in the TB install at the very end of the list at the left of the ACCOUNT SETTINGS tab ... and basically you can edit/change them from there if you want to, or you can also edit them from the selection list within the details for a specific account.

Is there something else which needs amending here? As I say, there are actually loads of SMTP 'accounts' in that list, I assume all from various additions of accounts to TB over the years.

The settings there I have for the two MS accounts that I'm trying to use are:

SERVER NAME: smtp.office365.com (but if I try and use smtp-mail.outlook.com which is what MS say you should use in their help pages, I get the same result - neither work) PORT: 587 CONNECTION SECURITY: STARTTLS AUTHENTICATION METHOD: OAuth2 USER NAME: the appropriate email address for the account

I can't find any other settings to change ...

As mentioned, my Gmail account is still working fine - it's just the MS ones which have stopped sending mail. I can still receive mail fine to all of them, and read it etc ... it's just when I try and send I get the 'Login to server smtp-mail.outlook.com with username xxxxx@hotmail.com failed' message (or the office365 server depending on which I use).

Oh, and you mentioned ADD ONS - I don't think I have any. None are showing as being there in the ADD ONS AND THEMES area anyway.

Thanks!!

David

Modified by david854

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Just out of interest, on a laptop, I tried a completely new install of Thunderbird ... it was not on the laptop before ...

And I added one of my Hotmail accounts.

And I get the same 'Login to server smtp.office365.com with usename xxx@hotmail.com failed' message when I try to send a message.

So this tells me it's not the PC I'm running on as it's happened on a 'clean' install to another device ...

It's either that Thunderbird is for some reason not supporting sending to Hotmail SMTP any more ...

Or that there's some issue with my Hotmail accounts - and I have checked the MS help pages, and checked what settings I have there ... and it all seems to match and be fine. They also work fine on my phone and through Outlook.

The settings in Thunderbird for the clean install are the same as the ones on the PC - this was set up on the laptop by using defaults etc - nothing has been manually touched or configured at all. So a clean install. Add the hotmail account, try and send a message ... fails.

Does that help track this down?

It's hard to believe that no-one else has this issue as it's so simple to create ... but I'm assuming there must be *something* in the config of my hotmail accounts (which I have had with the same settings for at least 20 years now) which is causing it ...

Can anyone help? Otherwise this is probably the end for me and Thunderbird which I have been using in various forms since around 1996 ... :(

David

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David, I have the same problem. I have 2 hotmail accounts working fine with thunderbird since the last 10 years... I'm in Win10 and thunderbird is 128.2.3esr (64-bit).

Settings for income POP:

Server Name: outlook.office365.com
Port: 995 
User Name: XXXX@hotmail.com
Connection security:  SSL/TLS
Authentication method: OAuth2
and
Server Name: smtp.office365.com
Port: 587
Connection security: STARTTLS
Authentication method:  OAuth2
User Name: XXXX@hotmail.com

I tried in a virtual machine a new install but stills not working. I googled for 2 days triying everything I find but not work for me. The problem starts this week (but not in the same day in my 2 accounts).

Microsoft make some changes in my accounts that thunderbid didn't like it. Hope they find a solution.

Best regards

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No further replies here ... and I still have the problem.

Everything works in Thunderbird but I cannot send emails to any MS account - Gmail works fine though.

I'm having to use Outlook now to send emails from, with Thunderbird to actually view and manage them (as it's a much better interface than Outlook) ... but it's a right faff ...

Does ANYONE know why emails cannot be sent from Outlook/Hotmail SMTPs?

David

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Microsoft decided to alter stuff again and it's not just the Authentication Method. Everything now has to 'Authentication Method: Oauth2' Cookies must be allowed in order to set up the oauth2 token. VPN must be switched off otherwise server thinks you are trying to hack account. If you maintain a website and use a program like Apache Xampp then you must switch it off until oauth token has been set up because the process uses the 'localhost'.

Account Settings must use the following: Server Type: POP Mail Server

  • Server Name: outlook.office365.com
  • Port 995
  • User Name: xxxx@hotmail.com
  • Connection Security: SSL/LTS
  • Authentication Method: OAuth2


Server Type: IMAP Mail Server

  • Server Name: outlook.office365.com
  • Port 993
  • User Name: xxxx@hotmail.com
  • Connection Security: SSL/LTS
  • Authentication Method: OAuth2


SMTP:

  • Server Name: smtp.office365.com
  • Port: 587
  • Connection Security: STARTTLS
  • Authentication method: OAuth2
  • User Name: example@hotmail.com
  • Settings > Privacy & Security

Check under Web Content -


Your microsoft account and your hotmail account need to have the same password. Info at this link says:

Can't sign in to Hotmail or Outlook.com? Notes: Your Hotmail or Outlook.com password is the same as your Microsoft Account password.

so please make sure they are the same - done via webmail account.

Then there is the case of the SMTP username = eg: hotmail email address.

When it comes to 'sending' - smtp in Thunderbird - it can only send using the 'primary' email address, so if you want to send using hotmail email address then make sure it is set up as the primary email address. You do this via the microsoft webmail account.

Once you have all these settings and got the password sorted.

Restart Thunderbird When you get the Microsoft pop up window asking for password, type it in and clickon 'Sign in'. You may then get another window asking to allow Thunderbird access to server - click on 'Accept'

Modified by Toad-Hall

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Chosen Solution

To check:

  • Tools > Developer Tools > Error Console
  • Click on the top left bin icon to clear the console.
  • Close Error console

Then try to send an email and wait for the failure. Open Error console

Post image showing contents.

If you see something like this:

mailnews.smtp: Command failed: 535 Authentication unsuccessful, SmtpClientAuthentication is disabled for the Tenant. Visit https://aka.ms/smtp_auth_disabled for more information

The link mentioned in error console : https://aka.ms/smtp_auth_disabled

That link goes to this location - I specifically include the info on 'enable smtp': https://learn.microsoft.com/en-us/exchange/clients-and-mobile-in-exchange-online/authenticated-client-smtp-submission#enable-smtp-auth-for-specific-mailboxes

If you as a user are not enabled for SMTP then it fails - switch on SMTP. https://support.mozilla.org/en-US/questions/1464666?page=2#answer-1676928


IF you see something like the following in error console:

mailnews.smtp: Command failed: 535 Authentication unsuccessful [MN2PR05CA0041.namprd05.prod.outlook.com 2024-09-25T20:33:37.105Z 08DCDD14E4ECBF59]; currentAction=_actionAUTH_XOAUTH2 SmtpClient.sys.mjs:602:19

mailnews.smtp: Command failed: 500 Unrecognized command 'Length: 7' [MN2PR05CA0041.namprd05.prod.outlook.com 2024-09-25T20:33:42.231Z 08DCDD14E4ECBF59]; currentAction=_actionAUTHComplete SmtpClient.sys.mjs:602:19

This error message means issue with sending email address/username not matching primary. I asked user to check 'alias' email address. Some people may have a hotmail email address and also that hotmail account allowed some additional/alias email addresses. In outlook.com microsoft account webmail. You need to check what is set up as the primary and adjust if necessary. Apparently, smtp username in Thunderbird needs to use primary email address.

For more info and response from user who had problem resolved including images : https://support.mozilla.org/en-US/questions/1465652#answer-1680641

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Toad-Hall you are a SUPERSTAR!!! I didn't know about the Error console, and I certainly wouldn't have known how to interpret the output.

My problem was indeed that the ALIAS on the MS Accounts was set to be PRIME for the address I actually wanted to use, rather than the 'base' MS email address ... Switching the MS one to be PRIME made the emails all start to send again!

My remaining question then, is how to get Thunderbird to use my 'Alias' email as the one that the recipient sees. I have tried changing the field in ACCOUNT SETTINGS - the Reply-to Address - but it doesn't seem to make any difference ... I have tried rebooting TB ...

SO THANK YOU SO MUCH!!!!! A simple solution to why it wasn't working ... dontcha just love MS!!

David

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To clarify the last note ... did some more experimenting. The REPLY TO address does work - so if I reply to the email, it uses the correct ALIAS/REPLY TO email addy to reply to.

My concern was that in the email display both the FROM and CORRESPONDENTS columns show the base MS email addy rather than the one I specified in the REPLY TO.

Is there a way to 'spoof' the email so it seems to be coming from the Alias email rather than the base one? (IE I'd rather people didn't see the base MS email at all, and only saw my Alias one.

David

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You should be able to send 'FROM' another alias eg: @hotmail.com providing that account uses the SMTP username which is set up as primary eg: @outlook.com.

Account Settings Email address: same one as the account 'Reply-to Address: set up the one to use when people reply back - same one as account.

Outgoing Server (SMTP): - must use the SMTP set up with username that matches whatever is set up as primary.

OK...I was a bit confused at first.....so start again....you have sent a test email using eg: 'From' Hotmail addy to another Live or hotmail addy, via the SMTP using MS addy. You want to see what a recipient of your emails would see and you say it says the recipient will see FROM and CORRESPONDENTS columns showing the base MS email addy - the one used in SMTP and not the account email address you chose as 'FROM'.

Have I got that right ?

re : The REPLY TO address does work - so if I reply to the email, it uses the correct ALIAS/REPLY TO email addy to reply to.

The 'Reply-to' email address is like a special header sent with your email, so when the recipient clicks on 'Reply' - it auto inserts the 'Reply-to' email address in the 'TO' field.


I'm always pleased to get feedback because understanding what MS is up to is always helpful.

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Thanks! And yes it is very confusing ...

So on this REPLY TO address thing ... I'll use fake emails here just because ...

So I have a domain fake.co.uk - this is set up to simply forward any emails it receives to fake@hotmail.com

So I therefore have a MS account fake@hotmail.com

My email address (that I want to use) is however david@fake.co.uk

In MS while I could set up an alias of david@fake.co.uk, if I set that as the PRIMARY, I cannot then access these emails via Thunderbird, because on Thunderbird, if I try and set up an account to 'read' emails from david@fake.co.uk, of course there are none there, as that domain does not hold any emails, it just forwards them on.

So to use Thunderbird I need to actually set it to access fake@hotmail.com. AND MS needs to have fake@hotmail.com set as the PRIMARY address ...

So ... I can access and send my emails fine via Thunderbird now ...

But ... I would prefer the REPLY TO address to be david@fake.co.uk - and I can do this by just setting the REPLY TO address in the Thunderbird Account Settings. This makes anyone replying to my emails, send them to david@fake.co.uk.

However, if I send an email to myself ... in Thunderbird (just to test it all), both the FROM and CORRESPONDENTS information contains fake@hotmail.com. I would prefer it if this said david@fake.co.uk ... ie no-one I send emails to can immediately see that there's actually an MS account involved here.

And I appreciate that if you dig into the message headers etc for a given email you WILL see exactly what's happening ... MS emails and all.

I was expecting, because I changed the REPLY TO, that, when that email arrived, it's FROM information would be the REPLY TO email address.

Can I get Thunderbird to change this 'FROM' information when I send an email?

In the SMTP element in Account Settings, there is a USERNAME, but I think this has to match the Username on as PRIMARY on the MS account ... so I cannot change that to be david@fake.co.uk. And there's nothing else obvious that can be changed in Thunderbird.

Maybe it's impossible to do ... I'm just asking in case there's some clever setting or method that allows it.

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I understand now. Let's assume you have created on MS an alias of david@fake.co.uk. That would mean you could 'send' with that email address and have the choice of setting that david@fake.co.uk as primary and then using it as the SMTP username for sending.

But obviously in Thunderbird, you would need to be able to choose 'From' david@fake.co.uk.

Try this: Create on MS an alias of david@fake.co.uk. For now leave the MS addy as primary - leave as is for now because you know it's working.

In Thunderbird In 'Account Settings' In left pane - Select name of fake@hotmail.com Bottom right - click on 'Manage Identities' Click on 'Add'

Enter all data For Email Address - david@fake.co.uk For 'Reply-to Address' - david@fake.co.uk Outgoing Server (SMTP) - select the same one as used by account fake@hotmail.com For Copies & folders' you can choose same as fake@hotmail.com OR use 'Local Folders' Check Composition & Addressing is all ok click on OK

Leave fake@hotmail.com identity as default click on 'Close'

Then restart Thunderbird to ensure all is properly updated.

Now when you use 'Write new message The 'From' should offer a drop down containing david@fake.co.uk

Use it to create a message and send. If you have a friend you can test with or another email address that would be ok or if you are a bit stuck then you can send to me a test message using this email address: mail at anje dot co dot uk I've written it phonetically to avoid spam bots - but where I say 'at' it means '@' and dot is a full stop/period In Subject put something like 'Test new identity' so I know it's you. I will respond by testing the 'Reply-to' and I'll post any other information in this forum. Please note, as a general rule I do not answer Thunderbird issues via personal email, but sometimes it's useful for testing or checking files etc. It's up to you.

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Hotmail/Microsoft do not allow alias addressing from mail clients. They fully support it if you use their web interface. They strip any information Thunderbird inserts in the message header regarding address name etc and replace it with the details of the primary address as recorded on their site.

So your domain at fake.co.uk SMTP mail server is going to have to do the sending of mail for anything you want to have appear as coming from @fake.co.uk email addresses. Although the domain does not appear to have a registered mail exchanger. https://intodns.com/fake.co.uk Without an MX record I am not sure how mail could even be delivered to any fake.co.uk address

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Toad-Hall - that worked!!! As you say, I just have to remember to set the FROM addy each time ... but the receiving email all works and shows as coming from the fake@fake.co.uk addy :)

And Matt:

Thanks so much for that. I did wonder if this might mean that Toad-Hall's suggestion would not work ... but it did! So maybe MS are not stripping everything out and replacing it as you say. Perhaps this bears further investigation.

And the word 'fake' I used was just a 'fake' domain for the example ... not the one I'm actually using. That checking site is interesting though :)

So ... for the moment, my problems are all resolved and I can use Thunderbird again!

THANK YOU ALL SO MUCH!! REALLY APPRECIATED.

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Hi all,

my Error Console shows this:

pop3.server6.3: Got an error name=oAuth2Error, the server said: undefined Pop3Client.sys.mjs:884:20

   _actionAuthResponse resource:///modules/Pop3Client.sys.mjs:884
   _onClose resource:///modules/Pop3Client.sys.mjs:452

pop3.server6.3: Got an error name=oAuth2Error, the server said: Connection is closed. 12 Pop3Client.sys.mjs:884:20

   _actionAuthResponse resource:///modules/Pop3Client.sys.mjs:884
   _onData resource:///modules/Pop3Client.sys.mjs:367

Config is: Server Name: outlook.office365.com Port: 995 User Name: XXXX@hotmail.com Connection security: SSL/TLS Authentication method: OAuth2 and Server Name: smtp.office365.com Port: 587 Connection security: STARTTLS Authentication method: OAuth2 User Name: XXXX@hotmail.com

I can't send and receive emails. Can someone help me?


Thanks in advance

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