What is the English translation of the error message? That may be of help. is the server set to port 587, STARTTLS, OAuth2?

Hello, I have 3 email accounts managed on Thunderbird. On one of the three (jeanmarie.doree@outlook.fr), I receive messages but I am unable to send them... while on the other two email accounts everything works normally. I deleted this account and reinstalled it but the problem is still there (see attachment). Thank you in advance for your help! Sincerely, JM Dorée

I do not know the error message. Would you please translate that to English.? Also, please post a screenshot of the SMTP server settings, as that may be a possible explanation. Finally, I am requesting this information on the possibility that such information will explain the error, but it may not.

Hello David, As I wrote to you, I have 3 email accounts managed with Thunderbird: jmd.ufc@gmail.com, family.doree@orange.fr and jeanmarie.doree@outlook.fr The first two work perfectly, but with the third (jeanmarie.doree@outlook.fr) if I receive emails, I can't send them... (see attached file: screenshot 1). I have also attached screenshot 2 and 3 of the account settings. Many thanks for your help ! Kind regards, JM Dorée

Change authentication to Oauth2 and let me know. That is required.

Bonsoir, Voir les 3 copies d'écran, suite à votre dernier message.

Bonsoir, Je viens de faire un nouvel essai et tout semble fonctionner à nouveau !!! Un grand MERCI ! JM Dorée

You are very welcome!  :) I sometimes wonder why it is that the French people are so polite - but I LIKE IT! I appreciate your courtesy and kindness in your posts and responses. You may assume this is normal, but it is not, and it is always welcome.

Yes dear David, the French are sometimes grumblers... but (in principle) polite. Especially when a nice computer scientist helps them... THANK YOU again!

Thank you for the smile. You're welcome here anytime.  :)