So you've embedded the tracking pixel in our outgoing e-mail, sent it, but still have no activity in your mail tracking? There could be different reasons as to why. Tracking pixels not collecting data may be caused by the following reasons:
One of the reasons that your tracking pixel hasn't collected any data is that the recipient simply hasn't opened its e-mail. This way the tracking pixel does not track any data. Make sure you haven't gotten any typos in the e-mail address though!
Your tracking pixel cannot function if the e-mail client of the recipients blocks images. A recipient may do this because of various reasons, for example saving on mobile data or because of privacy issues. That's why you want to make sure that the recipient trusts you.
Whenever your outgoing e-mails end up in the spam box of your recipients, it may not be tracked. This is because the recipient may not read e-mail from its spam folder or images from spam mails are blocked. This causes the tracking pixel not to track data.
Always make sure that you've embedded to correct pixel in your e-mail. Either the URL to the pixel or the html-code may be at fault. Prevent this by directly copying the URL or html-code.
In case you have blacklisted the IP-address of the recipient, then that recipient may not be tracked (if it opens the mail from the same IP-address). Learn more about the IP-address blacklist in How to prevent tracking yourself (IP-address blacklist).