src attribute of <img> is missing when sending mail

Question

I am trying to send a HTML mail from php that contains an image.

I receive the email and all the HTML tags look good except for the <img> tag.

The message of the email looks like this:

$message = '<img src="http://your-click.ch/wp-content/uploads/2014/11/logo1.png" alt="Your Click" width="131" height="52" border="0" />';

When I receive the mail, I see that there is an image but it is just blank. When I check the element, I see this code:

<img alt="Your Click" width="131" height="52" border="0">

As you see the whole src attribute is missing? Why?

Answer 1

Some email clients filter out externally linked images for security reasons. Try encoding the image and including it in the body of your message instead of externally linking it.

Answer 2

The image is probably being filtered by the recipient mail server, try base64_encode the image, i.e.:

$image = file_get_contents('http://your-click.ch/wp-content/uploads/2014/11/logo1.png');
$message = '<img src="data:image/png;base64,'.base64_encode($image).'" alt="Your Click" width="131" height="52" border="0" />';