Outlook and domain name

Hello

I have been using a domain name for my photo business which goes to a yahoo account and then I use outlook (full) to pick them up, all was good untill yesterday when I could not send emails, using paul@paulbaldry.com as the from email address.

I am forced to use the yahoo address in the from email box which means that people get an email from a yahoo account rather than paulbaldry.com and it don't look good.

What service can I use to send emails (SMTP) that will allow me to have the from address as my own domain?

And how does it work?

Thanks
Paul

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