I assume that adding some PHP will do this but I don't know where to start. I supply this link to an affilitate advertising operation where xxxxxx represents a unique code they generate to identify the unique source: http://abcwebsite.com/&subid=xxxxxx A visitor clicks on the link and my landing page opens. The visitor fills out a form and I receive an email containing entries made in the form (using mail()). I need the xxxxxx to be included with the email to identify its xxxxxx origin. I've searched for guidance, but can't find any. Any suggestions?
On your landing page (which I assume contains the mail form that the user fills in), you need to add a hidden field to the form, containing the subid: <input type="hidden" name="subid" value="<?php echo htmlentities($_GET['subid']); ?>" /> Code (markup): In your code which mails the form, make sure that it also sends the content of the "subid" form field, which will contain the subid sent via the click.