[BlueOnyx:25247] Re: 451 4.6.0 Alias expansion error

[Michael Stauber]

Hi Felix,

> Since a few days we occasionally are getting a “451 4.6.0 Alias
> expansion error” when sending mails to email aliases that before worked
> perfectly well.
> 
> Gmail for example writes: Delivery incomplete. There was a temporary
> problem delivering your message to xxx at xxxxx.xx. Gmail will retry for 47
> more hours. You'll be notified if the delivery fails permanently.
> 
> What could be the reason?

That happens if there are conflicting entries in the virtual host alias
mapping of Postfix.

This is not much to go by from what you've written, but I'd be glad to
take a look. Please send me the login details by submitting a "Support
Request" via the GUI with "allow access" ticked. And let me know the
email address that's causing issues in the description of the ticket.

-- 
With best regards

Michael Stauber