According to the invention, a method for detecting modification to a video content receiver within a content distribution system is described. In one step, a message is generated by a content provider. The message is sent to the content receiver by way of a network. The message includes an intentionally-inserted error that a normally-operating content receiver would detect. The message is check for either authenticity or authorization. The message is received by the content receiver from the network. At a point physically remote to the content receiver, it is detected that the content receiver failed to detect the intentionally-inserted error in the message.