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Thunderbird error message -unable to send mssages

Thunderbird Send and receive email
christ1 replied
jlewis1
jlewis1

Three days ago, when I tried to send a email using Firefox v128 and my main email account using my desktop PC, no message was sent but I got the following error message from Thunderbird:- 

   "Send message error.

   Sending the message failed. Outgoing server (SMPT) error. The server responded: No SMPT service for unauthorized users."

Five days earlier, I was able to send messages from my main account with no problems, and had not tried sending any more until the day this problem arose. I have tried sending a message via my main account a couple of times with the same result. I then found my laptop had developed the same problem

Incoming messages on my main account have arrived alright - no problems, so presumably my password is correct.

As far as I am aware I have not made any changes to the settings in Firefox on either computer. I can send and receive messages using my g mail account without problems. I have Windows 11 Home 24H2 (64 bit) on my desktop PC and Windows 10 PRO 22H2 (64 bit) on my (oldish) laptop. Both updated the day I found the problem, and it still persists. 

John Lewis
Three days ago, when I tried to send a email using Firefox v128 and my main email account using my desktop PC, no message was sent but I got the following error message from Thunderbird:- "Send message error. Sending the message failed. Outgoing server (SMPT) error. The server responded: No SMPT service for unauthorized users." Five days earlier, I was able to send messages from my main account with no problems, and had not tried sending any more until the day this problem arose. I have tried sending a message via my main account a couple of times with the same result. I then found my laptop had developed the same problem Incoming messages on my main account have arrived alright - no problems, so presumably my password is correct. As far as I am aware I have not made any changes to the settings in Firefox on either computer. I can send and receive messages using my g mail account without problems. I have Windows 11 Home 24H2 (64 bit) on my desktop PC and Windows 10 PRO 22H2 (64 bit) on my (oldish) laptop. Both updated the day I found the problem, and it still persists. John Lewis

All Replies (1)

christ1
christ1
  • Top 25 Contributor
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No SMPT service for unauthorized users

Apparently you need to authenticate to your email provider's server first. If you're unsure what to do about this, check with your email provider. Typically Thunderbird would prompt you for your account password when it's needed.