You should whitelist the domain in your e-mail account.

  1. Log in via webmail (GMail).
  2. Go to Settings.
  3. Go to the Filters Tab
  4. Add a new Filter
  5. Set it for "To:"
  6. Click "Set Up Filter"
  7. On the next screen, click the box for "Never send to Spam".
  8. Finish the setup.

This will ensure that Google never internally blocks a message from our own domain. It's a very common issue with Google's Spam settings.