Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Suddenly outgoing email stopped working - SMTP issue(s)

  • 36 cavab
  • 1 has this problem
  • 16 views
  • Last reply by sy777

more options

I've been using Thunderbird for many years with no problem. I'm now on v. 115.4.2 (64-bit). Suddenly, I can no longer send email. This is the message I get:

Sending of the message failed. An error occurred while sending mail. The mail server responded: <sy777@maine.rr.com> sender rejected. The email address you are sending as must match the email address you used to auth. Please check your SMTP settings. AUP#Out-1500. Please verify that your email address is correct in your account settings and try again.

I contacted Spectrum and received their recommended settings. The only difference I have is that my Authentication is set to NONE and theirs to YES OR CHECKED

My incoming email works fine.

Please help!

I've been using Thunderbird for many years with no problem. I'm now on v. 115.4.2 (64-bit). Suddenly, I can no longer send email. This is the message I get: Sending of the message failed. An error occurred while sending mail. The mail server responded: <sy777@maine.rr.com> sender rejected. The email address you are sending as must match the email address you used to auth. Please check your SMTP settings. AUP#Out-1500. Please verify that your email address is correct in your account settings and try again. I contacted Spectrum and received their recommended settings. The only difference I have is that my Authentication is set to NONE and theirs to YES OR CHECKED My incoming email works fine. Please help!

Modified by Wayne Mery

All Replies (16)

more options

The receiving server looks at your smtp settings to verify you are a legitimate sender and that it is not spam. The email address in the smtp server needs to be the same as in the email FROM address. So, the email address specified in the smtp server settings must match the server being used. For example, your maine.rr.com email address must be used with the appropriate server for that account, which is probably mail.maine.rr.com (assuming that is the proper name for it).

more options

David, Where in the TB smtp box does one enter his/her entire email address? On the grayed-out User Name line?

And again, should the word "smtp" be a part of the SMTP Name line?

more options

Click the 'edit' button and enter full email address in the User Name field. No, use only the smtp server name as provided by email host. Some email hosts put smtp in the name, others don't.

more options

Let me describe what I see in the SMTP box.

There are 4 lines. One of them is for the main email address and it's marked Default. User Name is my full email address for that account. There's a separate line for that account and under User Name stated <not specified>.

The remaining two lines are for the remaining email accounts and the User Name line contains only the username of the corresponding email address, it's grayed out and can't be edited.

The SMTP Server Name is the same as on my phone where incoming and outgoing email work just fine. There is no point in calling Spectrum again since I've already been told twice that they don't know what STMP is or stands for, and can't help me beyond verifying that webmail works. And it does. The rest of it, as they told me, had to be worked out with the app support.

I'm still stuck.

more options

It might help if you post a screenshot of this. I attached a sample of an SMTP setting and the part of the account pane that links to it. The account pane shows it is linking to the SMTP server whose description field contains the word 'Outlook' and that is the entry in the SMTP description field.

more options

Here are the screenshots

more options

Let me describe what I see in the SMTP box.

There are 4 lines. One of them is for the main email address and it's marked Default. User Name is my full email address for that account. There's a separate line for that account and under User Name stated <not specified>.

The remaining two lines are for the remaining email accounts and the User Name line contains only the username of the corresponding email address, it's grayed out and can't be edited.

The SMTP Server Name is the same as on my phone where incoming and outgoing email work just fine. There is no point in calling Spectrum again since I've already been told twice that they don't know what STMP is or stands for, and can't help me beyond verifying that webmail works. And it does. The rest of it, as they told me, had to be worked out with the app support.

I'm still stuck.

more options

And one more

more options

Three possibilities: - the syusim account does not show the full email address - neither account uses authentication, such as password - there is no descriptive name on either of them, making it possible that you do not have them linked to the right accounts. I suggest giving each a unique description and then looking at the account pane for each and check the bottom line of pane to see which SMTP server is assigned for each account.

more options

When you refer to the "full email address", are you referring to the greyed-out and not editable "User Name"?

In all my years of using TB, I've never used authentication for sending mail. When I successfully send mail via webmail, none seems to be required.

I made up descriptive names for each account, but I'm sure I knew which configuration went with which account even without it.

I made sure that all accounts use the same server, which is the same server used with webmail. If TB uses a different schema, I don't know where to find a different server name. Since it's outside of webmail, Spectrum was of no help.

Am I the only one with this problem that made TB unusable? There's got to be some kind of solution to this.

more options

Yes, the full email address. Email providers are more strict now than before and authentication is required by most. I get this question almost daily. You indirectly authenticate with webmail because you have to log in to your web account. The server name is the same. What is important is that each account have its own SMTP configuration. The error you reported in this thread is coming from your email provider, Thunderbird is just the messenger. Your email host is seeing the email from one account and the sender another account. After adding authentication and proper email address and descriptive name to each SMTP server, review each account pane to confirm that the account is using the designated SMTP server.

more options

So I have the same questions:

1. How/where can I enter a full email address if the User Name line is greyed out? 2. What should I make authentication to be? When I send email via Webmail, I enter the same password for each account in order to download new email. Then, when successfully sending email, I'm not asked for any authentication. 3. I've made up descriptive names for the SMTP server (the same server name for each account), but I don't see it making any difference. I use the same server name for each email address as when I use webmail.

more options

The website always works because the email provider's website is preconfigured. For a PC email client, you are responsible for the configuration and that is what I'm trying to assist with.

- the user name field is not greyed out in edit mode - the authentication should be whatever the email provider specifies - the purpose of unique descriptions is to ensure that when you are setting up the account that you are referring to the proper SMTP server. That was the reason for your post, to resolve that error message of using the wrong account.

more options

David, 1. Please look at the screenshot and notice that User Name (in the edit mode) is greyed out. 2. As I've said a number of times, I can't get any questions answered at Spectrum. As long as webmail works normally, everything else, incl. authentication (if any) is left to the client support. 3. I edited server names to comply with the one used with email. That is what one of your fellow supporters suggested I should do. All of my 3 accounts have used the same SMTP server.

more options

The User Name is greyed out because you've specified 'no authentication'. Set the authentication to 'normal password', as it should be, then enter the email address in the User Name box.

more options

Finally, it t seemed to have worked!!! When the password was requested, the one for 'retrieving' email worked.

Thanks a bunch!!! You've saved me and my patients!!!

S. Yusim

  1. 1
  2. 2