Many of our clients that are using @shaw.ca email addresses are not receiving emails from our servers.  The bounce back error we are receiving from shaw is:

Delivery to the following recipients failed.

     @shaw.ca

We have removed images, signatures, and everything that we can from our emails and have had no luck. My guess is that Shaw is blocking our IP address or our sending domains.  Do you have a postmaster we can contact to try to troubleshoot this issue?

Thank you