How can I use bluewin mail to send emails from an alias?

Chudolauck95

I have a lifetime redirection address from my university alumni community, which I decided to forward to my bluewin address. In order to send email from that address (and not from an "at-bluewin.ch" address) I decided to set up an alias in Thunderbird. However, whenever I try to send an email from the alias I get the following error:

An error occurred while sending mail. The mail server responded: sc301: Invalid sender address. Please verify that your email address is correct in your account settings and try again.

I believe this is a security feature in order to avoid misusing bluewin email. Nevertheless, I presume there should be a way to register my redirection address and prove that I am the "legitimate" owner of that address, hence I can use it as an alias. Does anyone know how to do it?

bitracer

You still need to set Bluewin username and password, just set "from" address to the forwarded email address.

Chudolauck95

Thank you @bitracer. I have done the same but I get the error message (Invalid sender address). Do you have a working setup? If yes, could you please share more details about your configuration?

bitracer

I don't have such setup with Bluewin, but that how this usually works. Have you tried a different email client?

Chudolauck95

No, I have only tried Thunderbird. But I did not see any option in webmail interface either.

I can guess that this might be a security measure (Swisscom don't want me to send email on behalf of any random person, naturally). So, I should somehow be able to prove that the forwarding email belongs to me before I can send emails via that alias. For example, to use gmail's "send email as" feature, I had to verify the alias/forwarding address by using a verification code that google sent to that email.