Cannot receive emails from Gmail

Cannot receive emails from Gmail

Hi, I cannot send emails from Gmail, however I can send emails from Yahoo accounts just fine.

I believe I have setup my mx records correctly, and I have verified my domain.

Here is the error that Gmail gives me (I have censored my domain)
Delivery to the following recipient failed permanently:

     brian@*.com

Technical details of permanent failure:
Google tried to deliver your message, but it was rejected by the server for the recipient domain *.com by *.com. [198.252.105.130].

The error that the other server returned was:
550-Please turn on SMTP Authentication in your mail client.
550-mail-qk0-f175.google.com [209.85.220.175]:34116 is not permitted to relay
550 through this server without authentication.