Why are some of my links not being tracked?
First, if you haven't done so already, see "How link click tracking works?"
Vocus.io will only track links that are masked. Naked links will not be tracked.
Notice that in the masked link example, the text "our website" takes you to a destination, and acts as a mask over that destination. Whereas in the naked link example, the text (http://example.com) is called naked, because it shows the destination.
The reason naked links are not tracked is because they give the user the impression that they will be taken to the destination URL, however end up being redirect to Vocus.io before sent to the destination. This behavior is consistent with patterns typically used by phishing attacks, and therefore could trigger some spam filters.
If you want your links to be tracked, make sure to always make them masked.