Are you sending Legitimate emails to clients with GMail accounts that are getting marked as Spam? Here is a few things you can advise the recipients:
- Check the spam folder in their Gmail accounts. If they find the message wrongly classified as spam, you can get it reclassified as not spam. Select the message, and click the Not Spam button that appears at the top and bottom of your current view. Unmarking a message will automatically move it to your inbox.
- If they emails are consistently being mislabeled as spam, you can prevent this by adding the your email address and details in to the contacts folder. It will then deliver the emails unless Googles filter knows with a very high certainty that it isn't spam.
- Create a filter rule that makes sure that any email sent by you to the recipient goes in to their inbox and is marked as not spam.
- Ensure that SPF, DKIM & DMARC records are setup in your DNS.
