When emailing from OpenCRM, you are seeing one of the following warnings:

• Warning: Your domain is not configured to allow sending from OpenCRM (Sender Policy Framework)
• Warning: Your domain is not configured to allow sending from OpenCRM (DKIM)
• Warning: Your domain is not configured to allow sending from OpenCRM (Sender Policy Framework & DKIM)

This warning is displayed when you are attempting to send from a domain (email address) that is not correctly configured to allow emails to be sent from your domain by OpenCRM.

You can still send your email, but it has a high likelihood of being flagged in your recipients' inbox as Spam or Junk

Please see : 

• Configuring your domain for OpenCRM (Email)