Malandrakis Angelos

Although it's been a long time since I installed virtualmin, I believe I installed it using the virtualmin install script. Regarding usermin, I installed it as a webmin module. Also, I don't know if it matters or not, but my server runs Ubuntu 18.04

It's a text box. Here is an image on how it seems (link)

It is from_format=1

Yes, it happens with all the users created through virtualmin

It's the latest version 1.823. I originally installed this just a few weeks ago

Actually it happens in all of these three cases. Whether I compose a new mail, reply or edit an old one, it always has the same address.

I apologize for my late response. I use the one that is next to this email in the postfix virtual users file (/etc/postfix/virtual). In this case it is the username "info.naxosrentacar" (created by the virtualmin)

No, mailbox address book doesn't have any entries at all. I opened this ticket as this problem seemed like a bug to me. However, if you believe that this is not a generic issue and it's a very specific thing on my server, I guess I should check this on my own, as it has to do with my server's settings.