Even if the From address is your default account, it will appear to be sent from gmail if the default account is set to send on the gmail smtp server. Open Tools/Account Settings, select the default account in the left pane, then look at the entry for Outgoing Server (SMTP) in the lower right pane. Is it set to the smtp server for the account or the one for gmail?

You may wish to send through the gmail smtp server, but unless you add the default (non-gmail) account to the gmail account on the Gmail website (Settings/Account & Import/Send mail as:), messages sent on the gmail smtp will be received as from the gmail address.

Yes the default Outgoing Server (SMTP) is set up to the default account not to gmail. And it still sends email from the gmail when I reply.

Also on my gmail account I have that other email address setup as default.

Any other suggestions?

Thank you, Zaya

Just to confirm your settings, select Help/Troubleshooting Information, click 'Copy text to clipboard', then paste it into a reply here, omitting all the printer and font data.

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   account4:
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     OUTGOING: , smtp-mail.outlook.com:587, alwaysSTARTTLS, passwordCleartext, true

   account5:
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     OUTGOING: , c17004.sgvps.net:465, SSL, passwordCleartext, true

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Accounts 1-4 look OK, but for account 5 you should have the gmail account sending on smtp.gmail.com, port 587, STARTTLS security, authentication = OAuth2, User name = your gmail address. In Account Settings, select Outgoing Server (SMTP) at the bottom of the left pane, then Add... the gmail server. Then, make sure the gmail account uses the gmail smtp server as described in my first reply.

I don't see how a message sent from your sgvps account could be sent by gmail, as there is no gmail smtp server. Always check the From: entry in the message composer, especially when you have multiple accounts.

I don't know if your sgvps accounts enforce strict association between the incoming server address and the outgoing server, i.e. whether you have to have separate outgoing servers for each account, or it's sufficient to use one server for all accounts.

thank you. I did add the smtp.gmail.com but it doesn't matter which smtp send as long as I have in the From field the default email account. Which is still not the case when I reply to an email, but it is the case when I compose an email.

thank you for trying to help with this issue.

maybe the problem is with the sgvps server?

The default account isn't of much importance in TB; it's mainly used by other applications, such as when you click a mailto link on a webpage. When you reply to a message, the default account won't automatically be inserted in the From address - the address of the recipient address is inserted. There are add-ons that help keep multiple addresses and identities organized - to avoid sending from the wrong one.

To minimize the chances of confusion with the sgvps server, I would create a separate sgvps outgoing server for each account, and ensure each account sends only on the associated smtp server.