Marketo secure tracking links give an insecure connection message when clicked, but this happens only when accessed from an internal corporate network.
If the error only happens on your corporate network, it is most likely caused by internal DNS routing that is specific to your network configuration. Work with your company's IT department to determine what changes need to be made to your DNS routing to resolve this issue.
Who This Solution Applies To
Customers using Marketo Secure Tracking Links