We have found the error.

The configuration was wrong.

in / etc/exim4/exim4.conf.template

missing the lines:

local_delivery:
extract {directory = $ {lookup {$ local_part }{:}{${ 4 @ $ domain} lsearch {/ etc/exim4/passwd }}}}/. maildir
maildir_format

Bye

Try to deactivate/activate Exim in the module "Features". After that create a test user and try to receive an email. If the problem appears again provide the Exim's log.

Hello,

That was the solution. Now eMail receive works fine, without changing the config by hand.

Thanks.