I am the guy who is experiencing the problem. If you look at post #5, I am showing exactly what I see in my Mozilla Thunderbird email client. The copy following "Link to ad:" is not coming through as a hyperlink. It is just plain text. It should be a clickable link to the product ad should it not?
My Thunderbird email client is working fine and this is the only email I can ever recall receiving where a URL has not been parsed into a clickable link. Did you open the actual email I uploaded in the zip file?