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Thunderbird uses wrong email addresses when sending an email + SOLUTION

  • 8 replies
  • 1 has this problem
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  • Last reply by teob69131

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I have the solution, but first here's the problem: I have two gmail accounts (call them A&B) and 2 yahoo accounts (Call them C&D) that have had no problem sending mail or getting replies to the correct email until about a week ago. The problem(s) that occurred recently are: I send an email from gmail user A, but when it get's to its destination the receiver sees the email address for B to reply to. Likewise for Yahoo, I send from C and recipient gets D's email address instead.

After scouring similar issues, all archived now, I tried their solutions. All did not work. Here's some details learned though:

Sending email uses definitions for a SMTP server. Until recently, I had no problems with email addresses being interchanged by Thunderbird, but as per some of the archives solutions I reviewed my SMTP definitions and noticed I did NOT have unique SMPT definitions for each email address! But now, this is a problem! So, how do you define unique SMTP definitions. Simply (right!) open ACCOUNT Settings and Edit the SMTP specifying unique addresses on the Outgoing Server. I was instructed to EDIT the SMTP Outgoing Server where I received a screen with a "Description" field and a "User Name" field. Instructions were to change the "User Name" by adding the account email address in front. Other solutions were to change the "Description Field" to the account email address. I tried each and both. What happens today is that when you change one of these for one email type, e.g., gmail, all the other gmail accounts change automatically to that newly modified change you made. In other words, ALL gmail accounts get changed to the new modification, So, I you change A, B will also change to the same information; likewise if you change B, A will duplicate it. Same with Yahoo accounts: change C and D also gets the change or D and C gets the change. There was no way around this behavior to make them unique.

SOLUTION: So, instead, I REMOVED one of the accounts, say account A and ADDED it back. NOW both A & B were unique. Same with the Yahoo C & D accounts after removing C and adding back. Problem after testing was resolved.

May I add that even worse problems occurred before the remove and add if you have told Windows 10 to default to Thunderbird as the email handler and you clicked on a Website's correspondence dialog to send an email. Then it NEVER sent the email to the expected recipient (Website owner) and instead sent it FROM either A or B, TO wither A or B, C to either A or B! I have retried this function since my solution change, so can't claim full victory yet. But, the removal and addition of an account back now supplies a unique SMTP automatically from Thunderbird.

Hope this helps you if you have the problems described.

I have the solution, but first here's the problem: I have two gmail accounts (call them A&B) and 2 yahoo accounts (Call them C&D) that have had no problem sending mail or getting replies to the correct email until about a week ago. The problem(s) that occurred recently are: I send an email from gmail user A, but when it get's to its destination the receiver sees the email address for B to reply to. Likewise for Yahoo, I send from C and recipient gets D's email address instead. After scouring similar issues, all archived now, I tried their solutions. All did not work. Here's some details learned though: Sending email uses definitions for a SMTP server. Until recently, I had no problems with email addresses being interchanged by Thunderbird, but as per some of the archives solutions I reviewed my SMTP definitions and noticed I did NOT have unique SMPT definitions for each email address! But now, this is a problem! So, how do you define unique SMTP definitions. Simply (right!) open ACCOUNT Settings and Edit the SMTP specifying unique addresses on the Outgoing Server. I was instructed to EDIT the SMTP Outgoing Server where I received a screen with a "Description" field and a "User Name" field. Instructions were to change the "User Name" by adding the account email address in front. Other solutions were to change the "Description Field" to the account email address. I tried each and both. What happens today is that when you change one of these for one email type, e.g., gmail, all the other gmail accounts change automatically to that newly modified change you made. In other words, ALL gmail accounts get changed to the new modification, So, I you change A, B will also change to the same information; likewise if you change B, A will duplicate it. Same with Yahoo accounts: change C and D also gets the change or D and C gets the change. There was no way around this behavior to make them unique. SOLUTION: So, instead, I REMOVED one of the accounts, say account A and ADDED it back. NOW both A & B were unique. Same with the Yahoo C & D accounts after removing C and adding back. Problem after testing was resolved. May I add that even worse problems occurred before the remove and add if you have told Windows 10 to default to Thunderbird as the email handler and you clicked on a Website's correspondence dialog to send an email. Then it NEVER sent the email to the expected recipient (Website owner) and instead sent it FROM either A or B, TO wither A or B, C to either A or B! I have retried this function since my solution change, so can't claim full victory yet. But, the removal and addition of an account back now supplies a unique SMTP automatically from Thunderbird. Hope this helps you if you have the problems described.

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teob69131 said

I'd just like to comment with My trials: 1. There seems to be 2 places SMTP servers are mentioned: A) When you go to accounts and look at bottom of all accounts at the "Outgoing Server(SMTP)" label on bottom left and B) If you go to Accounts and for a specific email address go to its "Outgoing Server(SMTP)" label.

That is correct.

Each has an EDIT function that functions similarly and each has the SINGLE SMTP Server name described which is common between all emails of a like email processor, e.g., gmail for all gmail accounts or yahoo for all yahoo accounts. These one does NOT change. Instead as you mention, there is a Description Field AND a User Name field. As I explained, changing either the Username or description which commonly equals the User Name is allowed. However if this is done ALL email accounts of that type, say gmail, change also to the changes you are making. So, that doesn't make them unique. RIght?

As I mentioned previously - there is only the one smtp and it is being shared. So you do not edit the username because it belongs to an existing account which uses it. Yes you can edit it because if there was an error in the spelling it would be necessary. That's why the instructions say for any existing smtp - edit the DEscription field so it says whatever is currently in the username as this will help to identify which account should be using it. If you did edit the username it would explain why you were not achieving the result you desired.

What will be important is to get each to have its own unique alias for the real and same SMTP server name, leaving the real one untouched. RIght? So, your instructions say ignore (B) method and dig into (A).

That is correct as this means you can edit the 'Description' on the current smtp to match the username, so you know which account should use it and also create a new smtp for the other account. And then make sure both accounts use their own smtp.

I may not have done it correctly, but know I tried the (B) method, probably incorrectly. It seems the trick is to always do an ADD of another SMTP "alias" for each of your gmails. RIght? Then ensure the Description AND User Name are the same for one of your single email addresses, but unique across all gmail accounts. Repeat for each gmail address specifying a new User Name different from others, but the same name in its Description field. Upon completion of all gmails you end up with an "alias" unique server name for each of your gmail accounts. How about that?

Yes. In cases where the server settings will be the same eg: person has more than one gmail email address. The 'Description' field helps the user to identify the correct smtp - to make sure the mail account is actually using the smtp for that account.

Well, where is the ADD function? you are referring to. I assume it is under "Manage Identities". So, you go to "Manage Identities" to do the ADD where you can specify the unique "alias" names Thunderbird will use to get to the real SMTP common name. Am I on the right track?

'Managing Identities' has nothing to do with editing or creating an outgoing smtp.

I mentioned this in my first comment - Bottom of Left Pane - select 'Outgoing Server (SMTP)' You are viewing the list of outgoing server smtp. This is where you can: 'Edit' the 'Description' field of an existing smtp to aid identfication. 'Add' another smtp. 'Remove' old disused smtp. 'Set default' smtp server. See image below as it shows an example of that view and you can see the list of available buttons on the right side.

.......allow Thunderbird to SIMPLIFY its design (no reason to have a method A and a method where SMTP OUTGOING is offered, and give the use ONE entry point to define unique "Alias" SMTP names. I have had no problem for decades with names other than from gmail or yahoo ever, and until this past year even yahoo had no issues. I hope my discussion can add your you instructions and hopefully make the process clearer for all.

When creating a mail account, it is normal/usual for a separate smtp server to be created. So I'm unsure as to why you seem to have only the one. But then you mentioned 'Manage Identities'. So I'm wondering if this has something to do with you adding email addresses as additional identities to an existing mail account. - But that is another topic.

Method A is where you can see the list of all your outgoing servers. It is where you can edit, add, remove and set as default.

Method B is the location where you choose which of the smtp is being used by that particular account. That edit function only gets access to specifically edit that preselected smtp server, so it should only be used when you know all your accounts are already using the correct smtp servers.

Personally, I think this method B of Editing seems to be causing a confusion. I do not see any problem as I know the difference, but clearly many people do get confused. So, perhaps the design could be improved.

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noticed I did NOT have unique SMPT definitions for each email address!

You had more than one gmail account using only one outgoing smtp server. So account A and B which had different gmail email addresses were actually sending using only B smtp settings. It is understandable how this could be a problem

Instructions were to change the "User Name" by adding the account email address in front.

I've never seen any correct instructions that state to change a username, because that smtp server is being correctly used by the account where the username = full email address of account. So, you would never edit the username.

Other solutions were to change the "Description Field" to the account email address.

Not quite correct but close - but there is a distinct difference between 'the accounts email address and the 'username' already set up in settings especially when there is only one smtp server and two gmail email addresses set up as accounts.

In the 'Description' field you type whatever is shown in the 'Username' field.

What happens today is that when you change one of these for one email type, e.g., gmail, all the other gmail accounts change automatically

Of course it changes on both - but only the description has changed not the actual smtp server - but why ?

Answer: because you have only got one outgoing server smtp being used by two accounts. And at this point you have only made it easier to identify which mail account should be using that particular outgoing smtp. You still need to 'Add' another smtp server for the other gmail account and then make sure both accounts are using their own smtp server.

Process: In 'Account Settings' - if you select the name of the account in the left pane and then look on the right side at the bottom you will see what outgoing server it is using. DO NOT use the 'Edit SMTP_Server' button because you are editing an smtp server which is being used by more than one account - you will be messing up that smtp server.

The correct method is to look in the LEFT pane - at the bottom below all the mail accounts- it will say 'Outgoing Server (SMTP)' at the bottom of the list.

  • select 'Outgoing Server (SMTP)'

This time you will the entire list of all your outgoing servers shown on the right.

  • Select the gmail smtp server in list to see it's settings.
  • Click on EDIT

It will have a username which = a gmail email address - one of your mail accounts.

  • Whatever that username says - type it into the 'Description' field and click on OK

so now the 'Description' = username

As you only have one smtp for gmail, it means you need to create another for the other gmail email address.

  • Click on 'ADD'
  • Enter the other gmail email address into the 'Description' field and into the 'User Name' field
  • Complete all the other server settings which will be identical to the original gmail smtp.
  • Click on OK

At this point you have two entirely different smtp's one for each email address.

Now you just need to make sure each gmail acount is actually using the correct smtp server.

  • select the gmail account in Left Pane and look bottom right to see the 'Outgoing Server' chosen. This is where the data entered into the 'Description' field is helpful.
  • If the email address of the account is the same as the Description of 'Outgoing Server SMTP' selected then it is ok.
  • If it is not correct, click on the 'drop down' to see and select the correct smtp server.

DO NOT use the 'Edit SMTP_Server' button.

When both accounts are using the smtp specific for the account - exit Thunderbird, wait a few moments for background processes to update and then Start Thunderbird.


So, when do you use that 'Edit SMTP_Server' button? You only use that method when you know you only have one mail account using it's own outgoing smtp server settings and no other account is using it. It will be a rare occasion when this is required as it is not a common practise for servers to change their smtp server settings.


The alternative is to follow the instructions posted - delete and add account again. Of course, it is still advisable to check the list of outgoing smtp servers to edit the 'Description' field.

It is not very easy trying to understand which account is using which smtp server when you have more than one account using same server settings. So use the 'Description' field to assist identification.

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Yes, I've seen these instructions many, many times and each time they didn't work as advertised. These instructions have been going on for years.

I'd just like to comment with My trials: 1. There seems to be 2 places SMTP servers are mentioned: A) When you go to accounts and look at bottom of all accounts at the "Outgoing Server(SMTP)" label on bottom left and B) If you go to Accounts and for a specific email address go to its "Outgoing Server(SMTP)" label.

Each has an EDIT function that functions similarly and each has the SINGLE SMTP Server name described which is common between all emails of a like email processor, e.g., gmail for all gmail accounts or yahoo for all yahoo accounts. These one does NOT change. Instead as you mention, there is a Description Field AND a User Name field. As I explained, changing either the Username or description which commonly equals the User Name is allowed. However if this is done ALL email accounts of that type, say gmail, change also to the changes you are making. So, that doesn't make them unique. RIght? What will be important is to get each to have its own unique alias for the real and same SMTP server name, leaving the real one untouched. RIght? So, your instructions say ignore (B) method and dig into (A). I may not have done it correctly, but know I tried the (B) method, probably incorrectly. It seems the trick is to always do an ADD of another SMTP "alias" for each of your gmails. RIght? Then ensure the Description AND User Name are the same for one of your single email addresses, but unique across all gmail accounts. Repeat for each gmail address specifying a new User Name different from others, but the same name in its Description field. Upon completion of all gmails you end up with an "alias" unique server name for each of your gmail accounts. How about that? Well, where is the ADD function? you are referring to. I assume it is under "Manage Identities". So, you go to "Manage Identities" to do the ADD where you can specify the unique "alias" names Thunderbird will use to get to the real SMTP common name. Am I on the right track? When I do all the above, I should be complete.

Well, some day I'll try the above + any changes to the instructions if I have a problem again. However, for my simple case where I had only 2 from a system, 2 gmail and 2 yahoo, each with the conflict, by removing one and adding the account back it was corrected. That is, the newly added one came in with an unique Description, Username, Identity than the messed up one I left alone. I may have been lucky and likewise with the Yahoo's too. So, I couldn't tell you which method I like without trying yours. I'm sure it works and in probably all cases. It just happened that my SMTP's were so screwed up already I couldn't get you instructions to correct it. But then, I'm not confident that I, like others from their comments, cold get it right. You method seems it should work in all cases. Mine worked in my case. I appreciate your response and crawled through it probably for the 10th time to determine what I missed. In either case, is Thunderbird serious in creating SMTP "alias" names that are unique when they get created? If so, Thunderbird must ensure they ARE unique, i.e., prefix by Username=Description. Then maybe it does this and I screwed up mine on my own somewhere. So, I'll accept your instructions, allow Thunderbird to SIMPLIFY its design (no reason to have a method A and a method where SMTP OUTGOING is offered, and give the use ONE entry point to define unique "Alias" SMTP names. I have had no problem for decades with names other than from gmail or yahoo ever, and until this past year even yahoo had no issues. I hope my discussion can add your you instructions and hopefully make the process clearer for all.

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Toad-hall, is there a usability bug report on file for this?

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Chosen Solution

teob69131 said

I'd just like to comment with My trials: 1. There seems to be 2 places SMTP servers are mentioned: A) When you go to accounts and look at bottom of all accounts at the "Outgoing Server(SMTP)" label on bottom left and B) If you go to Accounts and for a specific email address go to its "Outgoing Server(SMTP)" label.

That is correct.

Each has an EDIT function that functions similarly and each has the SINGLE SMTP Server name described which is common between all emails of a like email processor, e.g., gmail for all gmail accounts or yahoo for all yahoo accounts. These one does NOT change. Instead as you mention, there is a Description Field AND a User Name field. As I explained, changing either the Username or description which commonly equals the User Name is allowed. However if this is done ALL email accounts of that type, say gmail, change also to the changes you are making. So, that doesn't make them unique. RIght?

As I mentioned previously - there is only the one smtp and it is being shared. So you do not edit the username because it belongs to an existing account which uses it. Yes you can edit it because if there was an error in the spelling it would be necessary. That's why the instructions say for any existing smtp - edit the DEscription field so it says whatever is currently in the username as this will help to identify which account should be using it. If you did edit the username it would explain why you were not achieving the result you desired.

What will be important is to get each to have its own unique alias for the real and same SMTP server name, leaving the real one untouched. RIght? So, your instructions say ignore (B) method and dig into (A).

That is correct as this means you can edit the 'Description' on the current smtp to match the username, so you know which account should use it and also create a new smtp for the other account. And then make sure both accounts use their own smtp.

I may not have done it correctly, but know I tried the (B) method, probably incorrectly. It seems the trick is to always do an ADD of another SMTP "alias" for each of your gmails. RIght? Then ensure the Description AND User Name are the same for one of your single email addresses, but unique across all gmail accounts. Repeat for each gmail address specifying a new User Name different from others, but the same name in its Description field. Upon completion of all gmails you end up with an "alias" unique server name for each of your gmail accounts. How about that?

Yes. In cases where the server settings will be the same eg: person has more than one gmail email address. The 'Description' field helps the user to identify the correct smtp - to make sure the mail account is actually using the smtp for that account.

Well, where is the ADD function? you are referring to. I assume it is under "Manage Identities". So, you go to "Manage Identities" to do the ADD where you can specify the unique "alias" names Thunderbird will use to get to the real SMTP common name. Am I on the right track?

'Managing Identities' has nothing to do with editing or creating an outgoing smtp.

I mentioned this in my first comment - Bottom of Left Pane - select 'Outgoing Server (SMTP)' You are viewing the list of outgoing server smtp. This is where you can: 'Edit' the 'Description' field of an existing smtp to aid identfication. 'Add' another smtp. 'Remove' old disused smtp. 'Set default' smtp server. See image below as it shows an example of that view and you can see the list of available buttons on the right side.

.......allow Thunderbird to SIMPLIFY its design (no reason to have a method A and a method where SMTP OUTGOING is offered, and give the use ONE entry point to define unique "Alias" SMTP names. I have had no problem for decades with names other than from gmail or yahoo ever, and until this past year even yahoo had no issues. I hope my discussion can add your you instructions and hopefully make the process clearer for all.

When creating a mail account, it is normal/usual for a separate smtp server to be created. So I'm unsure as to why you seem to have only the one. But then you mentioned 'Manage Identities'. So I'm wondering if this has something to do with you adding email addresses as additional identities to an existing mail account. - But that is another topic.

Method A is where you can see the list of all your outgoing servers. It is where you can edit, add, remove and set as default.

Method B is the location where you choose which of the smtp is being used by that particular account. That edit function only gets access to specifically edit that preselected smtp server, so it should only be used when you know all your accounts are already using the correct smtp servers.

Personally, I think this method B of Editing seems to be causing a confusion. I do not see any problem as I know the difference, but clearly many people do get confused. So, perhaps the design could be improved.

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Wayne Mery said

Toad-hall, is there a usability bug report on file for this?

Good point. I'll check it out. The 'Description' field by default should be the same as the username field, just because it makes it much easier for identifcation.

Using the 'Edit SMTP_Server' button can cause lots of problems if more than one account is using that server and seems to cause confusion.

I do think this area could be designed to be more user friendly.

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Wayne Mery said

Toad-hall, is there a usability bug report on file for this?

I did locate this one: https://bugzilla.mozilla.org/show_bug.cgi?id=600856

It discusses that edit smtp issue.

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Excellent. I've hooked this up to the bug report

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Thanks Todd...Now I see that " 'Managing Identities' has nothing to do with editing or creating an outgoing smtp." and I with the image ("See image below as it shows an example of that view and you can see the list of available buttons on the right side.") you provided I got to the right Outgoing Server (SMTP) screen with an add function. Mine are indeed unique now, but the way did it was by chance I guess. I already had modified "alias "smtp names before that caused me the problems and by removing one of the 2 and re-adding account I got a default for the re-added one that was then unique since the previous one were already altered. Your way seems to be the total solution. A suggestion: 1. lead off with the Outgoing SMTP at the bottom of all the accounts and have user check there first for ALL unique "Alias" names. Remove any duplicate and add a unique one to be used noting which account it will apply to and name. 2. Then tell them to go to the account that will use this newly added one change the username and description to match the name added. Would that work? A much shorter process would be beneficial I think.

Again thanks Todd and others who contributed.