Changing email address gives rise to MSO Outlook issue

I am changing my normal email address from one I've had for many years from "mail.com" to a gmail address. I use MSO Outlook 2010 on my PC to handle my emails, both for my main email address and other, lesser used ones. Each address has a different Outlook .PST file. The main one, and the one for my current normal email address, being outlook.pst. I use POP email.

When I've changed to using my gmail address I want to keep using outlook.pst for my main email.

For, hopefully, ease of understanding, let's assume these are the email addresses:-

email-1 is my old normal address
email-2 is my new gmail address.

My plan has been to create another .pst file, email-1.pst, and setting it to handle newly received email for email-1.

Change the account details for outlook.pst to the email-2 account, both the normal details and the additional details.

This is working fine in that new email-1 emails go into the Inbox in email-1.pst, and emails sent from there are fine; new email-2 emails go into the Inbox in outlook.pst, and emails sent from that account are - almost - fine.

And there's the rub.

An email sent from email-2 goes out apparently ok, and looks ok to my son, a gmail user.

However if I send an email to myself from the email-1 account, Outlook shows in the From info

my_name <[email protected]>; on behalf of; my_name <[email protected]>

Looking at the email properties I see

Sender: my_name <[email protected]>
From: my_name <[email protected]>
X-Google-Original-From: "my_name" <[email protected]>
Reply-To: <[email protected]>

So despite me choosing the correct From email in the drop-down list it still uses the old email address in the From data.

I tried changing the default email account to email-2 (at) gmail.com but, even after restarting Outlook, it made no difference.

Thoughts on what I've done wrong would be most welcome.

This is normal behaviour for Gmail and nothing to do with your email client. It can't be changed.

If you send "From" an address which isn't your Gmail address, Gmail inserts the "Sender" header which triggers the "on behalf of" message in the Outlook client.

But I am sending from my gmail address, that's the issue.

Check in Outlook client's Account Settings and double check your "Email Address" and "User Name" are identical.

Yep, they're the same.

In Gmail webmail settings, do you have any secondary accounts listed under "Send mail as:" in "Accounts and Import"?

If so, delete them all.

I don't use Gmail webmail. All my mail on the PC is handled by MSO Outlook.

In reply to a post by cheshire_man:

I don't use Gmail webmail.

I know, but you have to go there to modify's Gmail's server-side settings.

Ah, thank you.

Gmail had email_1 at mail.com as the default Send As. Changed it to email_2 at gmail.com and it looks ok.

Many thanks.