We made a small mail list system. We want to know how many emails read by our users. So we insert a 1*1 pixel image hosted on our server in every email. We guess when users open the email then the image will be opened and the piwik on our server should monitor the image link. But neither the ‘goals’ nor the ‘download action’ can monitor this link.
Anybody can tell us the reason? And a good solution is prefered.