As mentioned in our March 4, 2015 release notes, we are in the process of transitioning out versions 2 and 3 of the ThousandEyes API. This transition will occur on June 4, 2015, at which point calls to either version 2 or version 3 of our API will cease to return data. If you've been contacted by members of the ThousandEyes Customer Success organization offering transition assistance, we strongly encourage you to take us up on the offer.