Hello

But now I'm stuck with the next problem: I set the registration to "only by admin" and sent access-information to two test-users, but they never received any mail... Any ideas on this?

Do you test your forum on a public server or on a local server at home? The forum uses the PHP function mail wich gives an email to the email server that is declared in the php.ini. If there is no or a not reachable emailserver declared, the email will not be sended.

You can use the function phpinfo that gives you various information i.e. these from the php.ini to clarify the state for sending emails.

Tschö, Auge