Always asks for password / does not send mail

[Igor-938]

Hi!

I have two kinds of problems that I explain right away.

1) When I try to download messages to my inbox I receive a uniform window asking for my password. I write the right password, select 'Use password manager to save password' and click ok. I download the messages correctly. Until here everything is fine.
But when I want to download a few minutes after other messages Thunderbird (5.2.3.0) ask me again for the password. How can I prevent Th from always asking me for my password?

2) When I want to send (by clicking submit) a message, this window will open with this message ...
'An error occurred while sending mail. The mail server replied: 5.1.0 <MYWEBSITE.COM> BODY = 8BITMIME SIZE = 1425 invalid address. Please check your email address in your account settings and try again. '


Yet I have not changed some parameters
How can I send messages normally?

Thanks

[DanRaisch]

1. Go to TOOLS > OPTIONS >SECURITY > PASSWORDS tab> SAVED PASSWORDS button and there you can delete the stored passwords. Restart Thunderbird to ensure that the stored password is cleared from memory. The next time you "Get Mail" Thunderbird will ask for the password and you can check the box to remember the value.

2. Have you checked with your email provider to ensure that the settings you have for the outgoing (SMTP) server match their current requirements. Although you haven't changed anything in Thunderbird, changes may have been made on the server side, particularly in regard to Authentication Method and Connection Security.

[Igor-938]

1) I have done as you told me to do but Thunderbird it always asks for the password.

2) The parameters of the provider for the account (the one that fails to send) are correct, I am sure because I have another email account (I call it "account B") with the same domain (es name@domain.com) that is set in the same way and works well.
I am also sure because I installed on another computer (Windows 10) Thunderbird same updated version 52.4.0 (32-bit) with the same mail accounts are the same settings and they both work well.

Can you give me any other suggestions please?

Thanks

[DanRaisch]

Who is the email provider?

[Igor-938]

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