Relatrix is able to track email opens by embedding a one pixel invisible image into the notice or newsletter once it is sent. When your user views the email and the images load, we count the email as 'opened'. You can see these results in your notices or newsletter module by clicking the email count after publishing has been completed. It typically is a good idea to wait on checking this number under 24 hours after completing the publish process to get a good idea of the total number of opens and the number of opens as a percentage of emails sent.
Email tracking can sometimes be deactivated if the user's email client doesn't allow the tracking pixel to load. For instance, if the recipient formats their email in plain text, if their email client doesn't automatically download images, or if their corporate filter strips away all images for incoming emails. This shouldn't happen often, but can happen from time to time.
Relatrix tracks email 'opens' in the Notice and Newsletter modules only. We do not track opens when you use the 'Email Selected' function from the Volunteer or Partner modules.