[ARCHIVED] Hyperlinks in emails end users receive

Whenever we use the feature to link a knowledgebase article in a ticket for a reply to an end user, when the end user receives the email about a ticket update, the hyperlink is no longer a hyperlink.  If the end user clicks the link for the ticket number, it opens up the ticket on the web version and the hyperlink is clickable.  I tested this with an agent submitting the ticket and the hyperlink is there in the reply email and they can just click the link without having to open up the ticket on the web.  Is there a setting in ZenDesk I am missing to enable this for end users?