forum does not send verification mails but does send failed login attempt mail

[JeanCremers]

I just set up the latest smf at forum.jcremers.com
The forum does not send verification mails but does send failed login attempt mail.
I have selected php mail.
Nothing relevant in the logs.
What could this be?
Thank you.

Hello Jean,
We have detected a failed login attempt on your account.
Matched forum members with same ip address:
[names removed]

[Deaks]

do you get other types of notifications from teh forum through email?

[JeanCremers]

so far this was all i got. Can i ask it to send mail somewhere?

[JeanCremers]

there are now personal messages in the mail queue but it doesn't want to send them.

[JeanCremers]

I got something in the logs:
Error: 503 AUTH command used when not advertised

[Tonyvic]

Can you not do the same as you discovered last year?
https://www.simplemachines.org/community/index.php?topic=569427.msg4029658#msg4029658

[JeanCremers]

That post turned up, much to my surprise, on a google i did.
I can neither get php nor smtp working at the moment, i contacted my provider, hope they know something.

[JeanCremers]

My provider gave me smtp settings but the forum acts funny. When i try to log in (with a different name to test) it immediately registers me in stead of saying 'an email is sent', although the setting is to activate by email. And then it stays on that page. If i refresh it it says user already registered. Getting nuts..