No idea who "Peter aka "Aelgmule", Sweden" is.

No idea when "Peter" tried to join. Don't know him. Or when "Peter" tried to join? Recently? Years ago? MikeH used to be a lot tougher rejecting applications than me.

"My e-mail is not accepted on that forum"?

So he claims his "email was rejected"? No idea what email that is. We don't "reject emails" either. For a period of time, google rejected nitroexpress.com email addresses, so Gmail didn't work on NE. Not the other way round.

"Apparently, I am not a real person and consequently I cannot register."
Huh? Sounds like the email address was not rejected .... But the application was.

Hint, when the application says the "Bio" is mandatory, a minimum expectation is a brief description of what the interest is and relevance.

I did reject a recent application because the bio was something like "I like guns" but the email was "easyemails", spammer sounding. I declined with a brief email "Apply again with a better BIO".

The system also times out applications after three days if they don't confirm their email address, e.g. if it was fuctious, or doesn't work.

Not our problem. Use proper email services

A reason we, cross fingers, are keeping spammers out.

The tone of that paragraph isn't endearing either .... But "Peter" can try again if he wishes.