I needed to send emails and automatically know when the receiver opens it. So I developed following system. Inside the email I put an image of this form: <img src="path_to_a_servlet?email_address=user123@example.com&email_id=987&text=bla bla bla" ... /> Code (markup): When image is loaded the servlet is called, passing it the parameters. Servlet registers in a DB that user123@example.com read the email 987 and returns an image with some text inside ("bla bla bla"). Such text is interesting for the receiver: in this way he is encouraged to accept external images in the email. This system works for every user, but one that uses Trend Micro antivirus and Outlook 2007. Trend Micro only reports to the user the email is a phishing attempt. Anybody knows how to avoid this problem? Some setting in Trend Micro configuration? Some special tag in the email? Using a .jpg URL in src attribute, instead of the servlet URL? Note that these are not malicious mails: receivers are employees and my system is approved by their companies. It's simply a way to make easier the reading notification. Thanks!