ruleset=check_mail, adress does not resolve

[justme11]

I get the next message when someone sent a mail to us, It is the right emailadress
Oct 19 10:42:16 sendmail sendmail[26372]: i9J8fveV026372: ruleset=check_mail, arg1=<...@noord-holland.nl>, relay=80-242-238-97.multikabel.nl [80.242.238.97], reject=451 4.1.8 Domain of sender address ...@noord-holland.nl does not resolve Oct 19 10:42:16

Do anyone know the answer?
Thnx
Marco

 

[Rhinokiller]

Check your DNS, MX and RDNS.

Cogito Ergo Sum - Non Compos Mentis