Webform module - Contact form will not send webform emails to users with the same domain, but will send to all other email accounts I set I have a Drupal 6 site. Using the Webform module. 

I have it set to send all submissions to the webform to my email address (me@gmail.com) and the clients email (tim@domain.com) - for some reason webform is not sending the email to tim@domain.com only to my email address. 

I tried different variations of emails, using other email addresses associated with the clients domain i.e. sales@domain.com but none of them work. But when I use other gmail and yahoo emails, the results come through just fine. 

Any ideas?
You using a shared hosting?  Could be that the recipients mail server is thinking your mails are junk if the originating mail is not coming from the resolved hostname.  This problem is common with shared hosting since they use virtual hosts.