[exim] Problem with ROUTER in exim.

Hellow,

I am a problem with my exim configuration.

I am a file "userfilter" with mails in the mailbox user, when I put a e
mail from my domain incorrect I see that the exim process do a loop:
for example.

ROUTER: adminforward -> usuario1@???
ROUTER: userforward_header -> usuario1@???
ROUTER: system_aliases -> usuario2@???
ROUTER: no_central_user_header -> usuario2@???
ROUTER: no_central_user -> usuario2@???
ROUTER: adminforward_header -> usuario2@???
ROUTER: adminforward -> usuario2@???
ROUTER: userforward_header -> usuario2@???
ROUTER: system_aliases -> usuario3@???
ROUTER: no_central_user_header -> usuario3@???
ROUTER: no_central_user -> usuario3@???
ROUTER: adminforward_header -> usuario3@???
ROUTER: adminforward -> usuario3@???
ROUTER: userforward -> usuario3@???
ROUTER: local_user -> usuario3@???
ROUTER: reinsert -> usuario3@???
ROUTER: system_aliases -> usuario3@???
ROUTER: no_central_user_header -> usuario4@???
ROUTER: no_central_user -> usuario4@???
.
.
.
.
.
and always the same... and the procces not end.


For example, the mailbox usuario3@??? is unknow... and the
system do a loop and no send the mail. I know that it is because the
user is unknow, because if I delete the mail usuario3@??? the
problem dissapear, but I dont know to solve the loop problem.