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Sudden onset can't send email on Thunderbird

  • 15 replies
  • 11 have this problem
  • 2 views
  • Last reply by GeneWo

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I like using Thunderbird, and have for years. Suddenly this morning I can't send emails. I can receive them, but I can't send them. My internet provider is spectrum and I have spent the last two hours with them trying to resolve the issue. No luck. I have verified the SMTP server and port, I have tried changing my password. The problem remains. When I send an email I get Log in to server mail.bresnan.net with my user name......failed. I can send and receive email directly through my Spectrum account (spectrum used to be bresnan) but hate having to log in 10 times a day just to see my email. I can't say I am computer literate. I have tried a restart, and turning my computer off. Neither helped. I'm hoping this is a simple fix, but I have no idea how to fix it. Spectrum did an update 2 days ago, I got FOUR Microsoft updates yesterday. Can anyone help? Thanks

I like using Thunderbird, and have for years. Suddenly this morning I can't send emails. I can receive them, but I can't send them. My internet provider is spectrum and I have spent the last two hours with them trying to resolve the issue. No luck. I have verified the SMTP server and port, I have tried changing my password. The problem remains. When I send an email I get Log in to server mail.bresnan.net with my user name......failed. I can send and receive email directly through my Spectrum account (spectrum used to be bresnan) but hate having to log in 10 times a day just to see my email. I can't say I am computer literate. I have tried a restart, and turning my computer off. Neither helped. I'm hoping this is a simple fix, but I have no idea how to fix it. Spectrum did an update 2 days ago, I got FOUR Microsoft updates yesterday. Can anyone help? Thanks

Chosen solution

Your last picture should have the full email address (user@bresnan.net) for the User Name, the authentication method = normal password, and the connection security = STARTTLS.

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All Replies (15)

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For the outgoing smtp, try mobile.charter.net on 587, STARTTLS, normal password, User Name = email address.

https://www.spectrum.net/support/internet/mobile-email-setup

Tools/Account Settings, Outgoing Server (SMTP) at bottom of left pane.

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Sorry, didn't change anything. Two additional pieces of information. Under Description there is nothing. <not specified> (don't know if that is needed or not) Under server name it shows mobile.charter.net

In the large box on the top it shows my email name-bresnan.net-mobile.charter.net don't know if that makes a difference or not? Thank you for your help. Will

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2mtl said

Sorry, didn't change anything. Two additional pieces of information. Under Description there is nothing. <not specified> (don't know if that is needed or not) Under server name it shows mobile.charter.net

The Description has no effect on smtp performance - it's for distinguishing multiple smtp servers.

In the large box on the top it shows my email name-bresnan.net-mobile.charter.net don't know if that makes a difference or not? Thank you for your help. Will

Not sure what this is - post a screenshot.

As a test, try the same settings for mobile.charter.net on 587, but with connection security = none and authentication = password, transmitted insecurely.

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Sorry, still no change. I am not sure I am competent to send a screen shot. I will try

Sorry, can't figure out how to do that, Can't copy and paste Tried Paint and I can get it there, but I can't copy and paste to this site. Following is a description of what I have on the screen.

Top of page

Outgoing Server (SMTP) Settings

When managing your identities you can use a server from this list by selecting it as the outgoing server (SMTP), or you can use the default server from this list by selecting use default server.


The following is in a large rectangular box. On the left hand side of the box it has buttons for

                                                            Add
                                                            Edit 
                                                            Remove
                                                            Set default

I have selected the settings you gave me as default. Below is the entire contents of the rectangular box. This is about the best I can do.

2mntl-mail.bresnan.net

2mtl-mail.bresnan.net

2mtl-mail.bresnan.net-mobile.charter.net (default)'

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Since you have multiple accounts with the same provider, you must set up the smtp servers with correct settings and different User Names, and set each account to send on the correct smtp server:

https://support.mozilla.org/en-US/questions/1350593

Use the Windows Snip app to make screenshots and save them to png or jpg format, then add them to a post by clicking the Browse... button below each reply box.

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Sorry to be so technically inept. I tried using different descriptions.....(a. b. c.) no change

The two emails with charter, have different email addresses, but both accounts use the same password. (not sure if that information helps)

I tried deleting all but one smtp account Changed one thing, but still cannot send email on Thunderbird.

When I used 2mtl-bresnan.net (as the only smtp account) I get prompted for a password, I put in the password and I get the log in to server failed notice.

Same result when I use 2mntl-bresnan.net as the only account

When I used the 2mtl-bresnan.net-mobile.charter.net as the only account, I get the message sending notice, (no prompt for password) but nothing happens, it just locks up. (Same with 2mntl-bresnan.net-mobile.charter.net)

I tried a second time and I get an immediate message that the message has failed, and another time I get the message that Thunderbird is currently sending a message wait? nothing happens. One notice said message sent blue line 100%, but then locked up and the message did not get sent.

I also tried everyone with starttls and normal password, didn't help. The last image is how my page is set up right now.


I don't really NEED more than one account to send emails (if that helps?)

Thank you for telling me about the snip function. I have attached the email fail notices (missed a couple) just hoping it helps some.

I really appreciate you trying to help me. I apologize that I'm not more computer literate.

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Chosen Solution

Your last picture should have the full email address (user@bresnan.net) for the User Name, the authentication method = normal password, and the connection security = STARTTLS.

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Windows 10, tb 115.3.3 (64-bit), out going server smtp-server.tampabay.rr.com, port 25. I use spectrum but I want to start using T-Mobile.

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Here;s another picture

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Sorry but I don't see your answer?

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GeneWo said

Sorry but I don't see your answer?

For tampabay.rr.com addresses, Spectrum recommends mail.brighthouse.com on 587, STARTTLS security, authentication = normal password, User Name = email address. If that doesn't work, try with connection security = none, authentication = password, transmitted insecurely.

https://www.spectrum.net/support/internet/spectrum-email-server-settings

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I will try again tomorrow but if didn't work

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Sorry but it didn't work. Please help if you can?

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And maybe set it up for t-mobile?

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It says I'm listed on spamhaus? https://check.spamhaus.org/listed/