topic Webmail rejects alternative identities in Email

Webmail rejects alternative identities

glocal — Fri, 25 Sep 2026 13:45:17 GMT

I think this applies to both Plusnet and Greenby's webmail.

On Greenby's webmail you can set up identities for outgoing email, and make them even the default. This is useful if you have your own domain and email addresses. But when I try to send an email this way, the server complains it doesn't recognise the identity. I am assuming that's because it looks like you are forging the From address, but there must be a way to do it, otherwise what's the point of Identities in Settings? Is there a way?

I think that was also an issue with Plusnet's webmail, but I haven't used it for ages and I can't remember.

Re: Webmail rejects alternative identities

PhilipHeyes — Fri, 25 Sep 2026 14:08:17 GMT

Via Greenby webmail or a Greenby SMTP server...

The identity has to be an email address or an alias that is part of your subdomain, create that via www.greenby.com

What Greenby have clamped down on is

1) sending without credentials

2) sending emails from email addresses or an alias that does not exist

3) sending from an email address that is not related to the credentials being used.

Re: Webmail rejects alternative identities

glocal — Fri, 25 Sep 2026 14:19:26 GMT

If I read this correctly we can use Greenby's webmail to send from name@account.plus.net but not something like name@mydomain.com. Is that correct? Not great but I can live with it because I hardly ever use webmail.

But are you also saying that I can continue using an SMTP client to send email as name@mydomain.com while Plusnet is handling outgoing email, but once Greenby takes over that function will stop? If that's the case, surely, there must be a way around it. Otherwise, I will ask Plusnet to move me back or pay another mail provider for 2 years.

Re: Webmail rejects alternative identities

MisterW — Fri, 25 Sep 2026 14:31:43 GMT

@glocal

f I read this correctly we can use Greenby's webmail to send from name@account.plus.net but not something like name@mydomain.com. Is that correct?

That is correct. You cannot send from a domain address that isnt hosted by Greenby and has a mailbox or alias configured for that address.

Otherwise, I will ask Plusnet to move me back

there is no going back, the whole idea behind the Greenby migration is that Plusnet will no longer be providing any email services

or pay another mail provider for 2 years

If you have your own domain, I'd suggest looking at Mythic Beasts https://www.mythic-beasts.com/hosting . It costs £20/yr (if paid annually) for email only hosting, plus £7/yr for domain registration.

Re: Webmail rejects alternative identities

PhilipHeyes — Fri, 25 Sep 2026 14:33:24 GMT

Send as name@mydomain.com via the SMTP server that accepts name@mydomain.com as the Username.

The whole point of improving the sender security is to prevent me or others from creating an email identity or profile where we send a forged email where the From is : name@mydomain.com

This is a gap that existed on Plusnet for decades and allowed buckets loads of forged spams to be sent.

Re: Webmail rejects alternative identities

PhilipHeyes — Fri, 25 Sep 2026 15:05:16 GMT

Once SMTP relay.plus.net transfers to Greenby expect the stricter sender policy and that may occur next week.

Re: Webmail rejects alternative identities

glocal — Fri, 25 Sep 2026 15:16:01 GMT

@PhilipHeyes wrote:

Send as name@mydomain.com via the SMTP server that accepts name@mydomain.com as the Username.

That would be Ionos in my case, presumably if I buy their email hosting service. I think this or similar cost should be covered by Plusnet, or Plusnet should run SMTP as it does now until the 2-year Greenby offer expires. Otherwise it's a non-offer for some of us..

Not to mention that they are also discontinuing the .co.uk for life domains they offered us as compensation a few years ago. There is no mention of any of this in their emails about the changeover, and after 20 years and 3 months with Plusnet I expected more transparency than that.

The whole point of improving the sender security is to prevent me or others from creating an email identity or profile where we send a forged email where the From is : name@mydomain.com

Yes, but name@mydomain.com doesn't have to be random. Greenby could accept outgoing emails from pre-registered From addresses/aliases. These would be associated with a legit, authenticated user and there would be a digital trail back to them.

Re: Webmail rejects alternative identities

glocal — Fri, 25 Sep 2026 15:17:45 GMT

Thanks for the heads-up. Time to raise a ticket now.