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Error sending email through alias/identity

  • 1 reply
  • 1 has this problem
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  • Last reply by Matt

Martin
Martin
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I have been using Thunderbird and the same private email server for many years. All my emails are forwarded to one central email address and I reply using an identity matched to the email address to which it was originally sent. I have never had problems using identities until after a Thunderbird update shortly after the beginning of March, 2020.

Now every time I try sending from an alternate identity, I receive an alert box which reads, "An error occurred while sending mail. The mail server responded: Sender address is not valid for your login. Check your email program settings.. Please verify that your email address is correct in your account settings and try again.."

I have tried deleting two different identities and adding them again, but I continue to receive the same alert. There have been no changes made to the private mail server. Any thoughts?

I have been using Thunderbird and the same private email server for many years. All my emails are forwarded to one central email address and I reply using an identity matched to the email address to which it was originally sent. I have never had problems using identities until after a Thunderbird update shortly after the beginning of March, 2020. Now every time I try sending from an alternate identity, I receive an alert box which reads, "An error occurred while sending mail. The mail server responded: Sender address is not valid for your login. Check your email program settings.. Please verify that your email address is correct in your account settings and try again.." I have tried deleting two different identities and adding them again, but I continue to receive the same alert. There have been no changes made to the private mail server. Any thoughts?

All Replies (1)

Matt
Matt
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My guess is you are in the USA where internet service providers have finally caught up with the rest of the world and refuse to se4nd mail for billy@whatsit.com for an SMTP server and login name for william@comcast.net.

You will need a dedicated SMTP outgoing server for each email address with the correct server used no mismatching of yahoo, Gmail personal domains etc. For example if you have a domain called mydomain your provider will have offered you an SMTP service for that domain. The exact rules each provider uses will differ. Domain providers usually allow any email address for the domain on a single login, you don't have to log in as billy to send billy emails. Others like Outlook./Hotmail will actually change the sending username and display name to those registered on their web site for the credentials used when logging into the SMTP server.