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Suddenly can't send email. Get Mailbox not available error

jenking77
jenking77
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Yesterday morning my email worked. Yesterday evening (and today) it does not. I can receive emails, but when I send them via Thunderbird I get the following message: "An error occurred while sending mail. The mail server responded: Request failed; Mailbox unavailable. Please check the message and try again." I have checked and double checked that the outgoing STMP information is correct. I have turned off my firewall and virus scanner (McAfee). I have changed my password with my email provider (att) and have updated the passwords in Thunderbird. I can send and receive emails from my phone and from the web version of my email provider. I can receive email through Thunderbird, but I can't send email. I hadn't changed anything when Thunderbird stopped working. I have NO IDEA what caused this and I have no idea what else to try. Please Help!

Yesterday morning my email worked. Yesterday evening (and today) it does not. I can receive emails, but when I send them via Thunderbird I get the following message: "An error occurred while sending mail. The mail server responded: Request failed; Mailbox unavailable. Please check the message and try again." I have checked and double checked that the outgoing STMP information is correct. I have turned off my firewall and virus scanner (McAfee). I have changed my password with my email provider (att) and have updated the passwords in Thunderbird. I can send and receive emails from my phone and from the web version of my email provider. I can receive email through Thunderbird, but I can't send email. I hadn't changed anything when Thunderbird stopped working. I have NO IDEA what caused this and I have no idea what else to try. Please Help!

Chosen solution

Do you have a reply-to setting? Removing this fixed the problem for me. My email provider is verizon (AOL).

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All Replies (5)

kaleidic
kaleidic
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Chosen Solution

Do you have a reply-to setting? Removing this fixed the problem for me. My email provider is verizon (AOL).

jenking77
jenking77 Question owner
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Thanks! That seems to have fixed the problem, but what if I want to have a reply-to setting? Why was it working fine and then suddenly stopped working? Any ideas?

kaleidic
kaleidic
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It happened after a Thunderbird upgrade, so it could be Thunderbird or something AOL did. Is your provider Verizon (AOL)?I submitted the error to Bugzilla. "It is a puzzlement."

jenking77
jenking77 Question owner
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My provider is AT&T so it's more likely something that the Thunderbird Upgrade did.

Jeannette_Prose
Jeannette_Prose
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I composed an email, then I get the error : The message could not be sent Using Outgoing (SMTP) smtp.suddenlink.net for an unknown reason. Please verify that your SMTP settings are correct and retry again. I have check my SMTP settings and they are correct and I have checked my password. All are correct. The just started all at once. I logged into my server account and I can send emails from there and from my phone.

Modified by Jeannette_Prose